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2017/09/20 [General] UID:1000 Activity:popular
9/20    

2009/1/7-12 [Science/Battery, Computer/SW/OS/OsX] UID:52329 Activity:low
1/7     new macbook 17" THE BIG ONE not the portable, has a non removable
        8 hour battery.  Dicuss.
        \_ it's like the airbook
           \_ no it's not, it's giant and i'm not going to carry that thing
        \_ stupid idea, will alienate customers.
         \_ Who will it alienate?  Assuming they can get longer battery
            life (both charge and number of charges) who cares?  So it costs
            an extra 100-200 bucks to change your battery but most likely
            you won't ever need to.  (I use my laptops pretty heavilly and it
            is only near the very end of their lives that the batteries start
            to go.  Give me 2x battery lifespan and that isn't going to be a
            problem.)  And if you do you save anyway because you replace the
            battery less often.
            \_ did you weld the hood shut on your bmw?
                \_ if the hood didn't need to be opened until 4 years later,
                   and the car had little economic life after 4 years, that
                   might be a better analogy. A better analogy might be that
                   cars use a lot more electronics than they used to, so a
                   2009 BMW is a lot harder to self-maintain than an '82 bug.
        \_ steve has syphilis and it's finally showing.
        \_ Why not?
        \_ Not as crazy as it sounds. I've only ever removed my battery to
           upgrade the RAM, and a 8 hour battery life is very attractive,
           since this past semester one of my classes was 2 hours and my
           macbook barely made it each time. --t
        \_ why are all these idiots sold on the 8 hours of battery life?
           \_ because apple has never provided that before
              \_ do they know you can get 8 hours of battery life with any
                 number of non-apple laptops?
                 \_ Not a thin(ish) top of the line, full power laptop with
                    a large screen.  It's hard getting 8 hours out of a
                    netbook.
                 \_ Yes. But choice of OS > battery life. I'd rather run OS X
                    than Windows, and with Linux I have the nasty tendency to
                    play with everything until I muck things up to the point I
                    have to reinstall (so I keep it on my desktop, which I don't
                    use as much, and can keep it working). --t
                    have to reinstall (so I keep it on my desktop, which I
                    don't use as much, and can keep it working). --t
2008/8/29-9/3 [Science/Battery] UID:50997 Activity:nil
8/29    I have 2 AA rechargeable batteries. One is at 300mAH and the other
        one is at 600mAH. They used to be 2400mAH. Is there anything useful
        I can use them for?
        \_ How do you know this?
           \_ http://www.amazon.com/Crosse-Technology-BC-900-AlphaPower-Battery/dp/B00077AA5Q/ref=pd_bbs_sr_1?ie=UTF8&s=electronics&qid=1220035985&sr=8-1
           \_ http://www.amazon.com/Crosse-Technology-BC-900-AlphaPower-Battery/dp/B00077AA5Q
              I love it. PS thanks for tinyurl this for me! I love motd
              tinyurl minions.
              \_ shortified
        \_ How long have you owned them?
2008/7/18-23 [Science/Battery, Computer/Companies/Apple] UID:50618 Activity:nil
7/18    iPhone battery life SUCKS. You'll probably have to spend another
        $100 in a year to get it replaced. Here's a cheap way to do it:
        http://video.gearlive.com/video/article/q407-replace-iphone-battery-tutorial
        http://www.anandtech.com/gadgets/showdoc.aspx?i=3036&p=3 (3G sucks,
                literally. Sucks up 25% more power)
        \_ no kidding.
2008/7/9-11 [Science/Battery, Computer/HW/Drives] UID:50518 Activity:kinda low
7/9     SSD don't improve laptop battery life:
        http://www.tomshardware.com/reviews/ssd-hdd-battery,1955.html
        \_ Already debunked, please go away mr one line on link.
           \_ Really, I read a couple of articles that said SSD don't
              improve laptop battery life, especially on the MBA. If
              you have a url to a debunking article, I'd like to read
              it.
              \- i looked at some numbers on power draw for various
                 components [for large machine room planning] and i
                 was surprised at how little power disks pulled. say
                 compared to even memory. so i am not surprised about this.
                 BTW, the design of the new Berkeley-NERSC computer
                 bldg and machine room is kinda interesting ... like the
                 choice of axis w.r.t. to the sun, the calculation of how
                 many days in the bay area the outside temp is lower than
                 the targetted temp inside the machine room etc.
                 \_ Is this over-engineering? I tend to think so, because
                    the contents of the room will change radically over
                    relatively short periods of time.
                    \- this isnt a machine room with 1u and 3u machines
                       coming and going. This is for "a computer" with
                       a 8 figure price tag.
                       a 8 figure price tag. and besides, the DoE actually
                       does "energy research".
                       \_ That "computer" will be obsolete in less than a
                          decade.
2008/6/12-13 [Science/Battery, Science/Space] UID:50236 Activity:nil
6/11    I got this as a google ad, I'm flabbergasted
        http://www.runsyourcarwithwater.com
        \_ So... we use electricity from the battery to electrolyze
           water, burn that gas, and use that power to charge the
           battery. And carry around this water as extra weight.
           Sounds great.
           \_ You wouldn't actually think this is for real, right?
2017/09/20 [General] UID:1000 Activity:popular
9/20    

2008/5/19-23 [Science/Battery, Academia/Berkeley/CSUA/Troll/Aspolito] UID:50009 Activity:nil
5/19    why are you such an ass aspolito? why dont you stick a D battery in
        your ars, dipshit
2008/5/18-23 [Science/Battery] UID:49997 Activity:low
5/18    I'm looking for a good rechargeable AA battery system. What do you guys
        use? I'm thinking of getting a bunch of AA NiMH and a really good
        charger that can do a full drain/recharge cycle to reduce memory
        effect as well as battery tender since NiMH seems to lose 10% charge
        per week, or AA Li-Ion with normal chargers. What do you guys think?
        \_ http://www.steves-digicams.com/nimh_batteries.html
        \_ http://www.candlepowerforums.com/vb/showthread.php?t=79302
           The candlepower guys are scary about batteries.  It's pretty
           strange how much variance there is between simalarly rated
           batteries, both in prefered load and total wattage.
        \_ I wouldn't bother with "regular" NiMH, unless your usage
           pattern is "charge, use aggressively within a week,
           repeat."  The obvious choice for the low-self-discharge
           type is the Sanyo Eneloop, but I've had success with
           cheaper Hybrio stuff (batteryjunction.com).  I hear the new
           MAHA Imedion are very good, too.  As for the charger, I own
           two MAHA C401FS as well as a MAHA C9000.  I think C9000 is
           a neat toy and useful at times, but most of the time, I
           stick to C401FS.  I hear LaCrosse charger is fine, too, as
           long as you avoid the earlier revision.
           \_ How's the usability for MAHA? I've heard a lot of bad
              things, like having to input 48 keystrokes to charge
              4 batteries properly. LAME.
              \_ Yeah, it takes fair amount of key presses to make it do
                 interesting stuff, but I don't find it annoying at all.
           \_ I recently got a LaCrosse charger, and love it.
           \_ Eneloops are awesome, now you can use rechargables electronics
              that don't need new batteries every month.
              \_ How are Eneloops different from other NiMH rechargable
                 batteris?  I bought the Eneloop package from Costco
                 (AA and AAA batteries and charger in blue plastic case), and
                 I'm using it just like the other rechargable batteries
                 (e.g. Panasonic NiMH) that I have.  I haven't been paying
                 attention at its performance.
                 \_ Regular rechargables lose charge very quickly even if
                    they aren't used.  (Like within a month.)  It makes
                    them pretty much useless for electronics that don't
                    get regular use (or have a low power draw).  Eneloops
                    on the other hand keep their charge for years.  Also
                    they seem to last longer under high draw usage than cheap
                    rechargables do, even ones rated the same mah or higher.
        \_ I don't use rechargeable. Alkalines are pretty cheap nowadays
           and they last 2-3X as long. Besides, 1.5V >> 1.2V. This whole
           1.2V thing really renders rechargeable useful for only a short
           amount of time before they drop to unusable voltage.
           \_ Alkalines drop to 1.2V very quickly.  Rechargables stay at or
              above 1.2V just as long as alkalines.
              \_ doubtful. I get about 30 flashes with a brand new NiMH
                 rated at 2200mA, whereas I get over 100 flashes with
                 alkaline. As a photographer, I can't afford to have to
                 switch batteries all the time, or an extra clunky 12V
                 NiMH pack at 5-8 pounds on my belt.
                 \_ http://batteryboulevard.com/alkaline-aa-15-volt-vs-nimh-aa-12-volt-smackdown
                    Also it really depends on the NiMH batteries you use.
                    \_ Again, whatever people say is still FULL OF SHIT
                       unless they provide an exact voltage/amp chart
                       of different appliances in respect to time. What is
                       the curve, drop off point, etc. You can't just say
                       X is better than Y or vice versa without knowing
                       exactly what the driving appliance is, and what the
                       useful voltage for that appliance is, and what the
                       chart looks like. Full of shit. Aspolito you're full
                       of shit as expected. Try again.
                       \_ Oh aren't you a cranky little pissant.  There are
                          plenty of battery geeks who have done voltage over
                          time charts that support me.  I frankly don't give
                          enough of a shit to hunt down the data for some
                          asshole.  Fuck it.  Keep using non rechargable
                          batteries.  It's not like they aren't a major
                          source of environmental damage and toxic landfill
                          waste.
                          \_ Ok I lied.  I do give enough of a shit.
                             http://www.powerstream.com/AA-tests.htm
                             \_ Cool link, and thanks for trolling, and
                                you're a fucking loser.
                                \_ People with any social skills apologize
                                   when they attack someone and are proven
                                   wrong.  You may want try it someday.
                                   \_ dude, you're STUPID
                                      \_ Are you saying he's stupid because
                                         he's still conversing with a dick?
                                         \_ you got trolled             !op
                                          \_ Trolls are still dicks.
                             \_ Thanks for the link.  It seems that NiMH
                                is superior to all but Lithium?  I guess
                                the Energizer Lithium is not rechargeable?
                                -jrleek
                                \_ Lithium batteries do bad things when
                                   recharged poorly.  Explosivly bad things.
        \_ On a somewhat related note, I have a MAHA C401FS and Maha Powerex
           and Duracell batteries I got a few years ago. I really haven't used
           them all that much (maybe 20 times). There was a period of
           maybe a year where I didn't use them at all. A few months ago,
           I had occasion to use them again, but the batteries and/or
           charger seem not to be working anymore (the batteries don't seem to
           hold a charge for long). I read recently that these NiMH batteries
           need to be charged on a regular basis, or else they lose their
           ability to hold a charge? This seems really lame. My batteries
           are only maybe 3 years old. Anyone else seen this happen?
           \_ I recently found some pretty ancient energizer NiMH batteries
              (6+ years old?) that I hadn't used for at least 3-4 years
              and they still seem to work well.
           \_ You need to 'refresh' them, ie, go through several
              charge/discharge cycle to bring back the full power.
              Some chargers like the LaCrosse do this automatically
              for you when you select that mode.
2008/2/11-14 [Science/Battery, Science/GlobalWarming] UID:49114 Activity:nil
2/11    "Scientists have invented the Prius of ocean-going submersibles"
        http://www.csua.org/u/kql (Yahoo! News)
        \_ submarines have been using 'hybrid' power systems since WWI, in that
           they  have batteries to run off of and diesel engines to recharge
           those batteries. Granted this was done not to save fuel, but to
           actually have motive power when underwater.
           \_ "submersibles".  Besides, it's not exactly a hybrid in the Prius'
              sense.  It gathers thermal energy from the ocean to power its
              propulsion, and uses battery power to run its controls only.  I
              guess it doesn't re-charge its battery by thermal energy or by
              any equivalent of regenerative braking either.  -- OP
              \_ the 'prius' reference in the article was completely off base
                 and uncalled for.
2007/10/2-5 [Science/Battery, Science/GlobalWarming] UID:48221 Activity:low 75%like:48218
10/1    Finally!  OLED Televisions
        http://www.breitbart.com/article.php?id=071001112033.l3kf86xb
        \_ Technology needs more development still.  But I'm glad this is
           finally rolling out.
        \_ 3mm thick?  Does it break easily just from moving around?  (Unless
           it's made of flexible material.)
        \_ I don't get it.  What use does a home user/consumer have for this?
           \_ While this particular model isn't remarkable, OLED has a lot of
              potential for televisions in general.  Compared to LCD, OLED sets
              should have wider viewing angles, response times two or three
              orders of magnitude quicker (so fast action on screen won't get
              blurry), and better display of the color black (all colors,
              really, but black is particularly bad on LCDs).  Early adoption
              aside, the way OLEDs are manufactured means they should also be
              cheaper to manufacture (once the production issues get sorted
              out, yields come up, and economies of scale kick in).
              \_ Thanks.  I wasn't seeing how super-thin was that big a deal
                 but the color, speed, etc, makes sense.  I get it now.
2007/10/2 [Science/Battery, Science/GlobalWarming] UID:48218 Activity:very high 75%like:48221
10/1    Finally!  OLED Televisions
        http://www.breitbart.com/article.php?id=071001112033.l3kf86xb&show_article=1
        \_ Technology needs more development still.  But I'm glad this is
           finally rolling out.
        \_ 3mm thick?  Does it break easily just from moving around?  (Unless
           it's made of flexible material.)
2007/9/20-24 [Science/Battery, Reference/Religion] UID:48135 Activity:kinda low
9/20    explain this whole Jena 6 thing for me.  ok tnx.
        \_ Black student asks for permission from principal to sit under so-
           called "White Tree," principal says sit where you like; next day,
           there are three nooses hanging from tree. Tensions rise, words are
           said, there's a fight, one of the (white) noose-hangers gets
           knocked out (but recovers in time to go to a school function that
           evening); prosecutor decides to prosecute (black) defendants for
           "Attempted Murder."
           \_ My understanding is the white kid who got beat up was not one
              of the noose-hangers but the whole thing has been so spun into
              the sadly typical OJ-like circus that who can tell?
           \_ and prosecutor decides not to prosecute the noose-hangers
              for a hate crime.
              \_ Actually, they were expelled, but then appealed.  Yes, there
                 is a difference between putting up some provocative rope and
                 beating the crap out of someone.
                 \_ Welcome to provocative speech, the kind of 1st Amendment
                    speech that does not protect you from assault and battery,
                    esp. when you're throwing punches as well.
                    \_ Does not compute.
                       \_ http://csua.org/u/jkl (ExpertLaw on A&B, mutual)
           \_ At first, I thought this was a troll about the porn star. My
              coworker briefed me about it this morning. -!op
              \- When i first saw "Jena protest" and "Jena 6" in print,
                 I thought it was a reference to something going on in
                 Germany. Jena is a famous old town prominent in German
                 cultural/intellectual/religious history, and also famous
                 for a Napoleanonic battle [hence the bridge in Paris from
                 the Eiffel Tower to the Trocadero is the "Jena Bridge"].
                 I was kinda surprised when I first heard it pronounced
                 "Gee-na". Did this story get natl coverage when the actual
                 events occured last yr? Or only after the trial. I was kinda
                 amazed to hear about the "White Tree of Jena".
                 http://en.wikipedia.org/wiki/Jena#Famous_citizens
        \_ http://www.csua.org/u/jkc
           Thank god they aren't locals, though...
2007/7/24-26 [Science/Battery, Science/Electric, Science/GlobalWarming] UID:47414 Activity:nil
7/24    Power outage in downtown SF. Lots of websites down.
        \_ Unable to surf, SF's civilization is down! CODE RED!!! Terrorism!
           \_ They got LJ, and now a million emo kids have nowhere to slit
              their wrists.
        \_ http://valleywag.com/tech/breakdowns/a-drunk-employee-kills-all-of-the-websites-you-care-about-282021.php
           \_ My old roommate drinks a lot and works there... hmmmmmm and is not online
           \_ FWIW I think the drunk employee story is a sham, but who knows.
              Just seems too much of a coincidence - drunk employee and major
              city power outage on same day?
        \_ D you know if affected Yahoo's webmail/addressbook/calendar services?
2006/9/28-10/1 [Science/Battery, Computer/HW/Laptop] UID:44592 Activity:nil
9/28    IBM/Lenovo announces recall of Communist Thinkpad batteries:
        http://tinyurl.com/kqa6h (ibm.com)
        \_ Sony to announce global replacement program:
           http://tinyurl.com/f8zsa (engadget.com)
2006/9/22-24 [Science/Battery, Computer/HW/Laptop] UID:44499 Activity:nil
9/22    Alan Cox's ThinkPad battery explodes:
        http://www.engadget.com/2006/09/22/another-thinkpad-battery-explodes
        \_ What happened to engadget lately? Their site used to look
           very professional, now it looks like it was designed by a
           20 year old. A lot of pictures just isn't resized
           correctly, you see the jagged lines, etc. Did I miss
           something? Gizmodo went down a similar path a year or so
           ago and I read it was because the guy left. What the hell
           happened to Engadget?
           \_ I noticed the same thing. I'm not sure what is going on
              at either site.  I have found that both sites do not
              play well w/ adblock plus in firefox (they look better
              in safari, but still not great).
        \_ It's essential to note that battery was bought off eBay, though
           it's an open question whether it was OEM or a knock-off.
           \_ Engadget did a site redesign just a few days ago.  I suspect
              bugs will be squashed over the next few weeks and it will
              start to look better.
        \_ It's essential to note that battery was bought off eBay, though
           it's an open question whether it was OEM or a knock-off.
2006/9/20-22 [Science/Battery] UID:44463 Activity:nil
9/20    Toshiba also recalling batteries:
        http://tinyurl.com/elvwl (csd.toshiba.com)
        \_ Damn, have all the problems been with Sony manufactured batteries?
        \_ Damn, have all the fucking problems been with Sony manufactured batteries?
2006/8/28-30 [Science/Battery] UID:44173 Activity:nil
8/28    http://csua.org/u/gs5 (pcmag.com)
        http://www.pcmag.com/article2/0,1895,2009199,00.asp
        Huge batteries and aggressive battery mgmt still don't give 4MB-shared-
        cache Core 2 Duo (Merom) based notebooks equal or better battery
        life over Core Duo (Yonah) - both 65nm.
        Need info on:  2MB-cache Core 2 Duo battery life and performance.
2006/8/15-17 [Science/Battery, Transportation/Car/Hybrid] UID:44009 Activity:nil
8/15    How ofter are you suppose to change your car battery?
        \_ Lead-acid batteries last about 5 years if well cared for.
           That means, it is never discharged more than 50% capacity,
           and is kept reasonably cool.  Depending on where you park
           (hot sunny spot?), how often you leave lights on, etc., the
           outcome will be different.  Just test it if you want to be
           sure.  Otherwise, carry a jump cable and wait until you get
           stuck somewhere.  And don't forget to recycle.
        \_ My battery's rated 60 months although I have to honestly say that
           I've never reached 60 months in the past 4 battery changes I've
           done in my life. I usually run them down, which is usually after
           3-4 years, call AAA when I need a jumpstart, and get a new one.
        \_ When it dies.  -average American male
2006/3/11-13 [Science/Battery] UID:42192 Activity:nil
3/11    Should Ni-MH batteries be occasionally discharged completely and if
        so, how often? Someone told me every 10-15 uses. Then again it might
        bi for Ni-Cd batteries, I forgot. Any help on this subject would
        be greatly appreciated, thanks!
        \_ http://www.nimhbattery.com see FAQs
           \_ any Li-ion faqs?
              \_ gawd, STFW.
2006/3/6-8 [Science/Battery] UID:42117 Activity:nil
3/6     Holy crap!  Yanni arrested for battery!
        http://news.yahoo.com/s/ap/20060307/ap_en_mu/yanni_arrested
        \_ So?  He does look like an ex-con in the mugshot.  Or are you saying
           holy crap he shouldn't have risked breaking his valuable fingers?
           \_ Like German John (and "Stanley"), Yanni is inherently funny.
        \_ It doesn't say anything about battery.
           \_ Second paragraph: "Yanni, whose legal name is John Yanni
              Christopher, was arrested early Friday and faces a domestic
              battery charge, according to a police report."
2005/10/21-24 [Science/Battery] UID:40214 Activity:nil
10/21   To extend the lifetime of your cell phone battery, is it better
        to leave them plugged in whenever possible, or to charge them only
        when absolutely necessary?
        \_ All the battery chatter I've heard so far is to not have it
           plugged in constantly but also not to let it drain completely.
        \_ For NiCd batterys, you are supposed to charge it fully when you
           charge it, and use it to empty before you charge it again.
           Otherwise it dies quickly.  That's called "memory effect" or
           something.  For NiMH and Li-ion batteries, supposedly you don't need
           to do that, but I do it anyway.
           \_ I've started seeing more manufacturer service advice suggesting
              to keep Li-ion on charge whenever possible, as the life is
              related to discharge cycle count and charge/discharge temperature
              (which goes up w/ current).  The main reason they aren't saying
              this outright is that customers would interpret this as being
              inconvenient.
2005/8/15-17 [Science/GlobalWarming, Science/Battery] UID:39124 Activity:moderate
8/15    Hack you prius w/ extra batteries to get ~ 80 mpg:
        http://www.treehugger.com/files/2005/08/wip_modified_hy.php
        \_ Similarly to the 110mpg claims, these are specious; the car
           with these mods is even less efficient than the stock Prius.
           You just don't see it as "per gallon" because you're getting
           energy off the grid, but that power comes from somewhere.  -tom
                    \_ "off" -> "from"
                       \_ peon
           \_ Yeah, it's kind of silly.  If you never engage the IC engine does
              that mean it's "infinity miles per gallon"?  Still, it'd a nice
              idea to extend a hybrid to behave like a pure electric until the
              juice is nearly gone and then kick in the gas.  Of course here in
              CA where we only burn natural gas for electricity...
              \_ Another argument for nukular power...
              \_ No.  Only 45% of electricity in CA comes from natural gas.
              \_ No, only 45% of electricity in CA comes from natural gas.
                http://www.pge.com/customer_service/bill_inserts/2005/july.html
                 Scroll to the bottom.
                \_ Wow, an actual informative post on motd.  Thanks for
                   correcting my misconception.
                   \_ What did you think CA was doing with their nuclear
                      power plants and hydro-electric dams?
 my ride'. WORD."                     power plants and hydro-electric dams?
                      \_ I was unaware of any working nuclear plants in CA.
                         I'd forgotten about hydro because I was thinking about
                         what were were burning for fuel.
                         \_ Diablo Canyon pics
                          http://www.zimfamilycockers.com/DiabloCanyon.html
                 \_ Am I reading this right?  They're planing on going
                    from 2% nuclear last year to 23% nuclear this year?
                    What?  How does that work?
                    \_ You're reading it wrong.   The right column is for the
                       whole state (in 2004), while the left column is for PG&E
                       only (in 2005).
                       \_ Ah, ok.
               \_ This is an excel spreadsheet of all the power plants in CA:
                  http://www.energy.ca.gov/database/index.html#powerplants
                  \_ Terrorists could use this info!  Oh wait, I forgot that
                     terrorists can only use public info if, by sheer
                     coincidence, hiding that same info might allow some
                     large corporation to hide something.
           \_ Yes, the 80mpg figures is meaningless.  But let's get around the
              meaningless figures and look at the facts that the silly writing
              is obscuring.  The article says "The extra batteries let Gremban
              drive for 20 miles with a 50-50 mix of gas and electricity."  So
              *maybe* it means the extra batteries increases the range by 10
              *maybe* it means the extra batteries extends the range by 10
              miles.  The small text in the picture says the (extra?) batteries
              cost as little as a quarter to charge.  So maybe it means 10
              miles per $0.25, or 100 miles per $2.50.  From a pure cost-to-
              consumer's point of view, this is much better than a stock Prius
              considering that gas is around $2.50/gal these days.
              considering that gas is around $2.50/gal these days.  I hope Mr
              Gembam, being an engineer, knows that he need to present the data
              in a clearer way that the author did.
           \_ It is not necessarily true that the power to recharge the
              batteries is coming from the power grid. He could have a
              solar setup at his house that lets him charge the batteries
              for the prius every night.
              \_ Solar?   at night???
                 \_ Solar systems charge batteries during the day so that
                    the energy can be used at any time (even night). The
                    batteries charging at his house during the day need not be
                    the ones charging in the car at night.
2005/4/2-5 [Science/Battery] UID:37047 Activity:nil
4/2     If I suspend a computer, can I change the battery? In another word,
        does the DRAM get refresh from the battery and if so, how many
        seconds do I have do change it?
        \_ No, yes, probably zero.
           Cool notebooks have a "bridge battery" for this kind of thing,
           but I haven't seen a bridge battery in years.
        \_ Use hibernate instead.
        \_ You used to be able to do this on PB/iBooks. You had something
           like 10 secs to swap out your batteries.
           \_ Still do, at least on my 1 GHz 15" PB G4. It's a very nice
              feature.
           \_ Just tried on my Toshiba (5 seconds). It failed. :(
        \_ just plug it in!
2005/3/5-8 [Science/Battery] UID:36538 Activity:low
3/5     So I want to buy an extra camera battery.  If I buy one with
        the name of the OEM on the battery, it's about $45.  If I buy
        one from a 3rd party, I can get it for around $12 and it has more
        Amp-hrs.  What's the deal?
        \_ I've heard that cheaps brand don't last as long and/or that the
           Amp-hrs they claim is not accurate, but I've yet to seen a
           study on it. Maybe consumer rights activists should benchmark
           these things . However, as you pointed out $12 is a good deal
           so it's probably worth the try. BTW I don't personally buy name
           brand anymore... you're mostly paying for the stupid name.
        \_ http://csua.com/Science/Battery
           Look for entry 12256 which has pointers to info on batteries
           \- The batties start to die upon mfgr, so I suspect some of the
              really cheap batteries are middle aged. For the Nikon D70, a
              Nikon branded battery is about $40-44. There are repuatable off-
              branded sources for $30 ... I image those will perform ok and
              not leak and destory your machine. Not so sure about the $8
              ones from ebay. I dont mind being out $10 for a poor battery,
              but I dont want something that will leak.
        \_ This is one reason why I chose a P&S camera that takes AA batteries.
        \_ I have a Canon 1100 A-Hr battery and a No-name 1800 A-Hr battery
           that I bought in Singapore. Both work fine w/ my 300D. However,
           the 1800 A-Hr battery has degraded a bit (fewer shots in a full
           charge) since I purchased it, but the 1100 A-Hr Canon battery
           seems to be able to take the same number of shots. I have used
           the 1800 A-Hr battery in many more cycles than the 1100 A-Hr
           battery, so perhaps the 1100 merely appears better b/c it has
           been through less cycles, I'm not sure
2005/2/25-27 [Science/Battery, Computer/HW/Laptop] UID:36420 Activity:nil
2/25    Stupid question, how is the 2300mah on my AA battery different
        from the 4500mah on my laptop battery? Is it the voltage? If I
        take 2 of my AA NiMH battery and add it up, the capacity is
        larger than my laptop battery's rated mah....
        \_ mAh is basically how much charge is available at a rated voltage.
           Total energy stored is maH*Volts.  Since your AA batery is 1.5V and
           the laptop's is around 15, the laptop's battery has about 20 times
           as much energy as an AA battery.  You could approximate a laptop
           battery with 2 columns of 10 AA batteries in series. (DO NOT attempt
           this)
           \_ what will happen?
              \_ Laptop batteries have 3 or 4 pins to allow them to monitor
                 and control charging.  Leaving these pins free is not in the
                 laptop design.  Also, laptop batteries are not exactly 15V,
                 some are 13.2 and others are 18.6 or whatever.  Getting it
                 wrong could let out all the smoke in your circuits.
                 \_ Feed the columns of AA batteries to the inlet for the AC
                    adaptor.
                    \_ OK, if you got the voltage and polarity right that
                       would work. -pp
2004/11/6-7 [Science/Battery] UID:34716 Activity:kinda low
11/4    Dear physics guru, say I have a device (phone, notebook, iPod,
        radio, etc) with a rechargeable battery. Is it best to keep
        them charged most of the time, or use them up and then charge?
        For example my cell phone has a standby of 3 days, should I
        charge up everyday, or wait till it's almost dead and then
        charge it up? Which one is better for the lifetime of the battery?
        \_ It depends on the type of battery.  For Li-ion batteries, the
           consensus seems to be that you should charge them all the time;
           they don't have a memory, and completely draining them is bad.
           \_ how about the 0859-0010, 4V 8AH Pure Lead Monoblock Battery?
2004/10/19 [Science/Battery] UID:34221 Activity:kinda low
10/19   I have a wierd problem, part of the little clip that keeps the battery
        in my cell phone has broken, so the battery falls out occasionally.  I
        want a good way to keep it in, of course.  Tape will look awful.  I've
        considered epoxying the battery door to the phone, but I'm worried that
        if the Li-Ion battery wears out, it'll be near impossible to change it.
        Is there some epoxy that can be dissolved with solvent, and which
        solvent will not damate the (polycarbonate?) plastic?
        \_ I believe epoxy solvents will not damage hard plastics.  Have
           you considered epoxying back the little clip, rather than
           the entire door?  -- ilyas
           \_ I'm missing a tiny chip of plastic that held the door on.
              I'm worried doing just the open button/clip might not be
              strong enough.
              \_ I think it would be easier to just find (or make) another
                 little chip of plastic, than epoxying the entire door
                 shut.  Another possibility is to make a form so the
                 epoxy itself will solidify in the shape of the little
                 chip.  It WILL be stronger than the surrounding plastic.
                   -- ilyas
                 \_ The epoxy chip idea is a neat solution until you look at
                    the actual phone and realize you'd need tiny mouse-hands to
                    make it work.  Thanks though. -op
                    \_ Can't you talk to the manufacturer and ask if they have
                       a replacement part or something?
                       \_ The broken part is a button built into the case.
                          It's not really replaceable.  If you're interested,
                          look up photos of the Audiovox VM4050, 9900 or 9950
        \_ Get some colorful rubber bands, like the kind women use for hair.
           \_ Won't work, it's a flip phone.
        \_ weird.
2004/9/22-23 [Science/Battery] UID:33707 Activity:moderate
9/22    Those of you with laptops and who frequently use them: how
        often do you have to recharge its battery? Is once/day too
        much?
        \_ 2 hours runtime with the base battery, 6-8 hours with the
           extended life battery.  Sharp Actius MM10.  -tom
        \_ I have a Pentium III 1.2 GHz notebook, and two batteries last
           4 hours.  One battery, two hours.  I believe any Pentium M notebook
           will last 3.5-5 hours with just the main battery.  This is assuming
           you aren't compiling or playing games most of the time but doing
           MS Word Powerpoint type work.
           I understand Pentium 4 based notebooks (mobile or desktop CPU)
           and mobile Athlons (even the new ones) suck power, so watch out.
        \_ My ibook gets me just under 4 hours on a full charge.
2004/9/19-20 [Science/Battery, Computer/HW/Laptop] UID:33625 Activity:high
9/18    how do i fix my thinkpad cmos battery?  i can't find
        the correct part to buy online.  is this something i can
        buy at radio shack?
        \_ watch out! I had a thinkpad where I thought the battery was
           busted, I bought a new battery, and it turned out that
           it was not the battery, it was something in the laptop's
           charging circuits or something.  new battery did not help.
           \_ he's talking about the CMOS battery, not the main battery.
        \_ get the FRU# from 1-800-IBM-SERV. Buy the part on ebay.
2004/7/26-27 [Science/Battery, Computer/HW/Laptop] UID:32488 Activity:moderate
7/26    I'm looking at Dell Latitudes, and there's an option for a 65W AC
        adapter vs. a 90W adapter which is $19 more. It doesn't give any
        explanation for what the higher wattage would be good for. The only
        thing I can think of that seems reasonable is if you want your
        laptop to power large USB devices or something. Can someone clue me
        in? Thanks.
        \_ The USB spec only allows something liek 5W of power to be sent over
           any single link of the bus.  The 90W adapter it probably so you can
           charge your battery faster, or run your laptop at full power and
           still charge the battery at full speed.
        \_ You might replace your HD with a faster/more power consuming one
           later, etc.
           \_ For thermal reasons you might not want to do that in a laptop.
        \_ http://csua.org/u/8by
           65W doesn't work with Latitude D800, but the 90W works for all.
        \_ I would urge you to look at the size of these things, and choose
           the one which is lighter and smaller, ignore the wattage
           requirement.
2004/5/6 [Science/Battery, Computer/Companies/Ebay] UID:30058 Activity:nil
5/6     i am shopping for digital camera's battery.  where is a good
        reputable place to get it?  i looked at ebay.  the prices are
        attractive but i don't want my battery to explode and damage
        my camera.
        \_ i just went to fry's to buy a spare for my canon s45
        \_ ebay, fry's, amazon, http://bhphotovideo.com
2004/3/19-20 [Science/Battery] UID:12771 Activity:nil
3/19    so why didn't the martian rovers use Solar Power cells so they
        can recharge and have endless trips instead of relying on batteries?
        \_ because solar isn't magic.  mars is much further than earth from
           the sun.
        \_ They do use solar. That's what all the panels on top are for!
           Did you somehow miss that?! --dim
2004/2/11-12 [Science/Battery] UID:12214 Activity:nil
2/11    I've been looking at NiMH batteries, and there seem to be some brands
        that are popular even though they seem like relatively small, unknown
        brands. Any recommendations on which brands to go with? Thanks.
        \_ I've been happy with my PowerEx AAs (2200 mAh).
        \_ first link for nimh battery (thomas distro) is a good site.
           typing in battery nimh takes you to the great battery shootout,
           also a good site. rule of the thumb: the more mah, the better.
2003/8/29-2004/2/14 [Science/Battery] UID:12256 Activity:kinda low
2/13    Any recommendations on which brand of NiMH chargers/batteries are the
        best value (in terms of having both reasonable performance and price)?
        I've got the AA and AAA sizes in mind. Thanks.
        \_ Someone asked this recently and I think PowerEx was reccomended.
        \_ Yawn, hasn't been updated for half a year at least
           http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM
2003/8/26-27 [Science/Battery] UID:29463 Activity:low
8/26    I just got a new NiMH battery for my thinkpad.  I'm going to use it
        occasionally, and I want it to last. Should I store it discharged or
        charged? I can't find anything on google or ibm. Thanks. -brett
        \_Return it and see if you can get a LiIon battery instead. NiMH
        is almost guarenteed to start failing within a year or two. If
        you want to keep it fresh you basically need to do a deep discharge/
        charge on it once it starts failing. I'm not quite sure if storing
        it away discharged will help the situation, as the batteries will
        degrade on their own over time. Storing it charged will not likely
        make much of a difference as the battery will lose voltage over time
        on their own, they actually will slowly leak electricty.
        The key thing is not to charge or discharge NiMH batteries in bursts,
        as they will have a memory effect.
        \_ I must be on crack, it IS Li-Ion, I don't know where I got the
           idea it was NiMH.  Thanks for the info and sorry about wasting
           your time. Ok, what about storing Li-Ion battery.   -brett
        \_ Re the memory effect, are you talking about NiMH or NiCd?
2003/7/14-16 [Science/Battery, Science/Electric] UID:29030 Activity:moderate
7/14    Do DC to AC power inverters cause any strain / damage to car batteries?
        Would the car battery wear out faster from continued use of the
        inverter?  Specifically, I'm looking at the Xantrex XPower 75 watt DC
        to AC inverter, available on http://buy.com at http://csua.org/u/3m8  If it
        does not damage the car battery or the device, is this a good price?
        \_ no, no, yes
           \_ Thanks for the validation.  Quick search on the web shows prices
              of $28-$29 for that model.  One site also showed 60W continuous,
              75W for 5 minutes, 150W surge for the XPower 75.  However, my
              laptop (Tecra 9100) requires 15V and 5A, so it seems it would
              only get charged for 5 minutes.  Is that the case, or would
              laptop batteries charge on 60W continous?  -op
              laptop batteries charge on 60W continuous?  -op
        \_ discharging your battery will destroy it eventually. loading your
           electrical system while the engine is running is fine, as
           long as your alternator isn't on its last legs.
2003/7/3-4 [Science/Battery] UID:28912 Activity:kinda low
7/2     hello have any of you used a solar charger for a laptop in
        particular a g4 mac powerbook 15"? do those supply enough juice
        to power a laptop or can they only trickle change the battery?
        ok tnx. --psb
        \_ There are some that will allow you to run a pb on solar
           power alone, but these are quite big and not portable (mostly
           designed for people who can find a good spot to camp out and
           setup a mini-solar array to power their computer). The ones
           that are portable provide only a trickle charge.
        \_ I'm not a thief; I pay for my energy instead of stealing it from
           the sun.
2003/6/24 [Science/Battery] UID:28826 Activity:nil
6/24    I have a ThinkPad with a dead battery/charger. It only works when on
        ac power. I want to take the Li ion out of the battery pack to cut
        down on weight. Any recomendations on how to do this? I've read
        that Li-ion batteries are dangerous. How so? what to look out for?
        \_ how old is this laptop?  The new thinkpad's have very easy-to-
           access batteries.
2003/5/31 [Science/Battery, Computer/HW/Drives] UID:28593 Activity:high 50%like:28598
5/31    I had another hard drive failure recently, making this 2 drives over
        2 years that have failed in under a year.  (And they weren't even IBM
        deathstars)  Is there any independent website logging failures
        to keep manufacturers honest about their MTBFs?
        \_ Could be your environment. Have you checked your powersupply lately?_
        \_ Could be your environment. Have you checked your powersupply
           lately?
        \_ SARS?
        \_ You using a battery backup?  I think that helps make your power
           better too.  I've had two hd crashes / slow death before, but not
           in the 5 years since I started using battery backups.
        \_ what brand do you use?
        \_ could be the heat, get extra fans to blow on them.
        \_ what drives are they?
2003/5/6 [Science/Battery] UID:28353 Activity:moderate
        2.4 Ghz, it means that there's a range of frequencies near 2.4 Ghz
        that it's transmitting and receiving.  If so, isn't it true that as
        more people get the same kind of phones the more likely you'll get
        crosstalk and bad reception?  Anybody happen to know the range of
        frequencies that a typical phone uses?   Thanks.
        \_ My impression was that 2.4 Ghz was just an idea to appeal to the
           guy who thinks that more hertz==better.  I've used many of both
           and my favorite *by far* was a 900Mhz uniden-- no static, no
           crosstalk, no problems.
                \_ Your impression is wrong.
           \_ My 900Mhz Uniden's battery runs out after fifteen minutes
              of talk time.  What the hell?
              \_ Mine is a lead-acid battery that wears out after several years.
                 If you pop open the battery casing you can probably find a
                 serial number; type "uniden battery" along with that # into
                 google and and you can find some quality resellers... I
                 replaced mine with a longer per-charge battery for about $18
                 incl. shipping.
                 \_ Good advice, will give it a shot.
           \_ Yeah, use what works.  2.4 GHz is a range that isn't regulated, so
              it's clobbered by X10, 802.11 and other products.  I'd rather not
              have a phone that interferes with my wireless network.
2002/12/26-28 [Science/Battery, Consumer/Camera] UID:26919 Activity:kinda low
12/25   Just got a digital camera that uses AA. The batteries die after 30
        minutes (Coolpix 2000). Should I go NiCd, NiMh or LiIon? Or exchange
        the Coolpix 2000 for the 2500 (+$60)?
        \_ If you like your current camera, go for the NiMH batteries (check
           out http://steves-digicams.com for your camera review). The 2500 seems
           pretty cool...but with most things, get the best that you can
           afford - depending on your level of interest in photography.
        \_ Regular batteries have too much internal resistance and so the
           camera will see dropping voltage very quickly as it draws
           significant amount of current.  NiMH will do you good here.
        \_ 1850mAh NiMH should do the trick. $13 at Amazon/Circuit City.
           \- for AA in flashes i use Varta batteries. might try those. --psb
2002/8/26-27 [Computer/HW/Laptop, Science/Battery] UID:25695 Activity:nil
8/26    I want to work outdoors for longer than my battery life.  any
        recomendations for solar laptop power supplies?  I saw quite
        a few on the web, but i'd rather not buy some expensive thing
        if i'm not *sure* it will work.  has anyone here done this?
        \_ what about an extra battery?  What about powering your
           laptop with alternate sources like a car battery or something
           like that?
           \_ or a foot pedal?
                   \- is there relly something like that?
                      that would be pretty cool for long remote trips.
                      i know there is a flashlight you can charge with
                      human power. ok tnx.
        \_ saw something like this at Fry's in Sunnyvale. Fry's is great
           for try-and-buy, as long as there's no restocking fee.
2002/7/26-28 [Science/Battery, Computer/Networking] UID:25429 Activity:very high
7/26    Any local places that recycle alkaline batteries for free?
        \_ Another offtopic question -- how to get rid of used up acetone?
           Since it has a half-life of 22 days in sunlight, and evaporates
           easily I just left it in the backyard in a canteen and it was
           all gone in a day.  Is there a better way?
           \_ I work in a lab where we use a lot of acetone.  We have all
              kinds of rules we have to follow to make sure that the
              organic solvents are disposed of "properly" , but
              as I understand it, it all just gets burned in the end.
              I'm sure there's a better way, but what you're doing is no
              worse than the EPA-approved official disposal method.
        \_ A little offtopic, but here's my chance to put in that
           the rayovac renewal (rechargeable alkaline) batteries work very
           well for many purposes.
           \_ How is it different from the old rechargable NiCd ones?  -- yuen
              \_ They don't lose their charge in storage, and their voltage
                 graph is sharper over time (consistently high voltage
                 and then a sudden drop-off means that your CD player will
                 just turn off instead of producing poor sound).  They
                 also don't have memory, so you can recharge them at any
                 point in their drain cycle.  They last longer per charge,
                 but their useful life cycle is lower than NiCd.  Cadmium
                 is _really_ toxic, alkalines less so.
                 \_ mmm, yummy... cadmium!
                 \_ Are they 1.5V or 1.2V?  Are they available in AA and CR123A
                    (camera battery) sizes?  About how much do they cost?
                    Thanks.  --- yuen
                    \_ I already know about (and have) these batteries. They
                        purport to be 1.5V and come in the normal 1.5V alkaline
                        sizes, like AAA, AA, C, D (I tihnk they come in the last
                        two, anyway). 4 AA's are like, ~$5-6 at fry's. -op
                    \_ op doesn't work with cable modem.  Or dsl. check out:
                        http://www.epa.gov/etv/pdfs/vrvs/06_vr_rayovac.pdf
                        \_ why do cable modems need batteries?
                           \_ for when the power goes out.
                              \_???  UPS.
                                \_ Yeah, but what about when the UPS goes?
                                   \_ Yeah how long is your dinky battery going
                                      to last if your 3 hour UPS can't handle
                                      it?  5 minutes?  Big deal.  Sometimes,
                                      you're just fucked and have to deal with
                                      it.  "five nines" just costs too damned
                                      much.
                                      \_ Apparently, it does work with
                                         UPS.  But it doesn't work with
                                         cable modem.  Cable modem just
                                         gets your account sorried.
        \_ Throw em in da Bay.
           \_ Why don't we cut em open, prop your mouth open with a crowbar, make
              you swallow them, and have your stomach acid handle the
              neutralization? Oh, and it might be interesting to watch too.
                \_ Someone a little constipated?
                \_ Econazi to the rescue, eh?  Get a clue.  It was a joke. Duh.
                   Everyone else knew that.
2002/4/15-16 [Transportation/Car/Hybrid, Science/Battery] UID:24444 Activity:very high
4/15    How often do people usually replace their car batteries?  My car
        battery died this morning even though I didn't leave any lights on.
        It's the original battery since I bought the car new in 1996.  Thx.
        \_ that's reasonable.  2-4 years perhaps, and if you drive short
           distances more than long distance, battery life can be shorter.
           Its time to get a new battery, though seeing if the battery
           can hold a charge can be a good idea if the battery is newer
           than, let's say, 3 years.
        \_ My car battery lasted for 7 years, and it died because my
           starter went all wonky.  I'm probably an anomaly. -geordan
        \_ It could be your alternator, too.  Never hurts to check.
        \_ Or distributor cap and rotor.
        \_ about every 7-10 years.
        \_ The deal should replace it for you ever three years or so.
        \_ The dealer should replace it for you ever three years or so.
        \_ 5 Years, typically... if you don't abuse it.  Then again,
           depend upon where you are.  I heard that battery last a bit
           longer in a colder climate.     someone flunked ChE176
                                           \_ not to mention E190.
        \_ i had a battery last 10 years in an old toyota truck. current
           audi will probably only make 5.  i blame the alarm etc. for
           sucking juice while the engine is off.
2002/2/13 [Science/Battery] UID:23856 Activity:nil
2/12    My VAIO laptop seems to be hosed.  It runs fine on AC power, but
        randomly shuts off when running on battery power.  I'm pretty sure
        it's not the battery because this behavior has been repeated with
        several different batteries.  Does anyone know what might cause
        this sort of behavior?  Does anyone have any experience dealing with
        Sony support or service centers?  It looks seems painful and
        expensive.  Should I just give up now, use the VAIO as a paper weight,
        and sell one of my kidneys on the black market to fund the purchase of
        an iBook?
2002/1/25-26 [Science/Battery, Science/Electric] UID:23665 Activity:very high
1/24    How do UPS's (uninteruptible power supplies) work?
        \_ trained hamsters inside only run when they see the little
           light go out.
           \_ Damn, products evolve almost too fast these days.  My old
              version only uses rats.
        \_ Big rechargeable batteries.
        \_ They sit between your box and the power grid, and are supposed
           to figure out when there's a drop in power, and then kick in
           within a short enough time to prevent the connected device
           from powercycling or experiencing damage.  Some also do surge
           protection, or are controlled by the protected machine itself
           (so for example when the charge is very low, they tell it to
           nicely shut itself down.)  -John
           \_ More like "conditioned" power. Drops are just as bad as spikes.
        \_ http://www.howstuffworks.com/question28.htm  --erikred
           \_ That's a GREAT web site!!!  -- yuen
2001/9/21 [Science/Battery, Computer/HW/Laptop] UID:22565 Activity:nil
9/20    When putting laptop in storage; i heard you should disconnect the main
        battery; but; should you leave the main. batt. charged and
        disconnected, or drained and disconnected?  How will this affect the
        cmos battery?
2001/4/23-25 [Science/Battery, Science/Electric, Science/GlobalWarming] UID:21069 Activity:high
4/22    Windows device driver engineers needed.  -jeffwong
        /csua/pub/jobs/Transmeta
        \_ With this posting, transmeta is now officially in the
           "We've given up competing, we are now trying to sell out to
            microsoft/intel/amd" category.
            \_ How does having Windows drivers constitute selling out?
               If they expected all of their users to use Linux, they'd
               be out of business already.  Look how successful the Linux
               distro companies have been.
               \_ because one of the claims was that they could
                  just transparently replace (from a software point of view)
               \_ D00D R3D H4T RUL3Z! 7H3Y W111 D357R0Y M$ 4ND 7H13R
                  U53R5 4ND RUL3 7H3 W0R1D! 1N5T411 17 B3F0R3 17'5 T00
                  L473!
               \_ because one of the claims was that they could just
                  transparently replace (from a software point of view)
                  an intel chip for massive gains.
                  Seems it's not such a perfect replacement if they need
                  custom drivers, eh? Start looking for a new job, jeff.
                  I give you 1, maybe 2 good years there.
                  \_ Average length of employment of an engineer in the valley
                     these days is between 18 and 24 months.
                     \_ That average is skewed because of the high
                        concentration of dot-bombs in the valley. My point
                        being that transmeta looks to be another one.
                     \_ Really? I was at Cisco for 4 years and I was
                        still a "junior" in terms of years of service.
            \_ Perhaps because their "low-power" designs were not so
               spectacular after all. TM chips ran at lower power at
               the expense of performance and we all know that what
               matters isn't power but energy (E = P*t) consumed
               by a laptop. If a chip consumes energy at half the rate
               of another but runs at half the speed, which one would
               you buy?
               \_ D00D CRU053 15 7H3 B357 CH1P 3V3R M4D3! 11NU5 541D 50
                  0N 11NSUX.K3RN3L! CRU053 B3475 7H3 P4N75 0F 1NT31 4ND
                  4MD, M070R014 4ND D3C! 37337 R3D H4T GN00/11NSUX 15
                  W1CK3D F457 0N CRU053!
                \_ What percentage of your apps are CPU-speed limited?  -tom
                   \_ A process doesn't have to be CPU bound to benefit
                      from a faster processor tom.
                        \_ It has to be CPU bound to use the same amount of
                           power in the equation above.  I think for the
                           vast majority of real-world applications, a slower
                           chip is better in a laptop.  -tom
                           \_ Why? So you have IE running as an I/O bound
                              process. Now a user clicks on a button and
                              something happens. IE executes a short task.
                              On a TM it takes 2 seconds while on another
                              processor it takes 1 but for the most part
                              they consume the same amount of energy
                              because TM's power consumption is half of
                              the alternative. The TM loses in this case.
                              EDP (energy delay product) is a better metric
                              for power efficient devices like this because
                              it factors in performance and not just power
                              and energy.
                                \_ CPU is almost always starved for data
                                   these days.  The speed of Netscape/IE is
                                   virtually unaffected by CPU speed
                                   difference--they're always waiting for
                                   disk or net.  The difference between
                                   200 Mhz and 400 Mhz is enormously larger
                                   than the difference between 400 Mhz and
                                   800 Mhz.  Why do you think people stopped
                                   buying PC's?  -tom
                                   \_ At least on PIII there is a noticeable
                                      difference between 400, 550 and 600.
                                      Beyond 600 I tend to agree with you.
                                      An athlon 1.2 GHz is not that much
                                      faster than a 600 because you can't
                                      give it enough work to do in most
                                      cases or it blocks on device io.
                                      I believe that the future belongs
                                      not to single fast procs but to
                                      multiple cheap slow procs. MPP
                                      is the way to go.
               \_ It dynamically lowers its voltage and frequency according
                  to your workload.  Why would you want to be running at
                  the maximum clock rate when you're typing or reading a web
                  page?  That is a waste of energy. Besides, a PIII laptop
                  can't go very fast when it's batteries are dead.
                  \_ I'm not defending the Pentiums either. Personally, I
                     think Intel sells crap. But most processors today
                     (at least those concerned with power savings) employ
                     power savings features during idle periods like clock
                     gating or disabling input latches to unused units.
                     Power consumption during idle periods by the CPU is
                     rather inconsequential compared to power drawn by a
                     spinning disk, LCD monitor, DRAM refresh, and other
                     crap running. I doubt TM chips fair much better during
                     idle periods than other alternatives.
                     \_ I'm not defending the Pentiums either. Personally, I
                        think Intel sells crap. But most processors today
                        (at least those concerned with power savings) employ
                        power savings features during idle periods like clock
                        gating or disabling input latches to unused units.
                        Power coproperly phrased question.   here, I'll put
                        you out of your misery:
                        http://arstechnica.com/reviews/peripherals.html
                     \_ D00D U R 50 WR0NG! CRU503 R0X! R3P3N37 UR B45PH3M35
                        W4Y5!
2001/2/22 [Science/Battery] UID:20643 Activity:nil
2/21    Someone must have wanted to do this before me:
        I'm going on a week long backpacking trip.  I want to take my digital
        video camera with me and do a lot of filming.  I could buy a BUNCH of
        batteries but i'd prefer to bring along my charger and rig some sort
        of a micro-generator. (something lighter than a car battery).  Ideas?
        \_ Blair Witch 3?
        \_ hrmm... I think I've seen like Brookstone or Skymall or something
           have hand-powered battery rechargers for everything from rechargeable
           niCad AA batts to most cell phone types.  I've also seen crank type
           generators for flashlights at sharper image if you want to do some
           rewiring.
        \_ Will professional battery packs sold e.g. at http://bhphoto.com solve
           ypur problem?
           \_ http://www.bhphotovideo.com  -brain
        \_ Any solar rechargers?
2000/9/18-19 [Science/Battery] UID:19275 Activity:moderate
9/18    What is the best rechargeable AA battery? I.e. the one that packs
        the most milliamp-hours. URL?
        \_ I've used 1600 mA hr NiMH batteries in my camera.  I've seen
           1500's at Radio Shack and 1600 at CompUSA, they're not hard to
           find --oj
           \_ Are they 1.2V?
             \_ Yes.  Which makes the "battery life" indicators give
                misleading info --oj
                \_ So I suspect a 1600mAh 1.2V battery lasts somewhere between
                   80% and 100% as long as a 1600mAh 1.5V battery in a camera
                   with both analog and digital components.  Is that right?
                        \-with a camera. especially a flash, i would strongly
                        encourage using batteries especially for photo gear
                        such as the varta batteries. they have a much sharper
                        power drop off, so your flash goes from charging
                        "instantly" to not at all ... rather than charging
                        taking longer and longer. --psb
           \_ this 1.2V shit is stupid. Can't use it on 80% of the devices
              \_ I heard this too, but my Sony Discman works fine on 2 x 1.2V
                 AA's.  Which devices really can't use 1.2V batteries?
2017/09/20 [General] UID:1000 Activity:popular
9/20    
Berkeley CSUA MOTD:Science:Battery:
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