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| 2005/3/1-3 [Computer/HW/Display] UID:36475 Activity:kinda low |
3/1 Yesterday, the BBC World Service did a review of the Mac Mini and
the reviewer noted poor-quality greyed-out video on his VGA monitor.
Anybody here noticed the same thing? I've read forums that
say that the Mac Mini produces non-standard video signal.
\_ Friend of mine just go this, and the video looks beautiful on a
PC VGA monitor. -John
\_ Use DVI
\_ Sure, that is probably a good idea, but for monitors
that don't connect to DVI (like a normal CRT), that is
not an option. and since the Mac Mini is advertised as
as working with "ANY OLD VGA MONITOR" I would like
to recommend a Mac Mini to my friends who have so many
problems with their Windows XP systems. $499+999 > $499
\_ No problem w/ a Sony 17" VGA CRT or a Apple 15" LCD
\_ No problem w/ a Sony 17" VGA CRT or a Apple 15" LCD. It might
be a problem w/ the DVI-VGA adapter. See here for more info:
http://tinyurl.com/6csfm (discussions.info.apple.com)
http://www.xlr8yourmac.com/feedback/mac_mini_dim_video.html |
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| tinyurl.com/6csfm -> discussions.info.apple.com/webx?14@1008.qgava8HfTER.4@.68a64fff/117 Joined: Jan, 2005 Posts: 5 Hi, I bought a Mac mini to replace my aging B&W G3, and I'm havi ng some video issues. I use an IOGear USB KVM switch with VGA inputs connected to a Samsung 213 T LCD. The Mac mini needs to use a DVI-VGA adapter to connect to the switch . And when I switch back and forth from the mini to the G3 either of my PCs , it's obvious that the mini is putting out a substantially darker signal t han the other two machines. No amount of fiddling with the calibration settin gs seems to help. Whites look gray, it's just dark and not pleasing to the e ye. I connected the Samsung directly to the mini via VGA with the same result s If I connect the mini directly to the Samsung's DVI input, it looks fine. I thought at first that the DVI-VGA adapter was to blame, but my Apple stor e replaced it with no effect. With much hassle and effort, I actually took my mini and screen to the Apple store to demo the problem, and we even hooke d my screen to one of their minis with the same results. The Apple store gu ys essentially just said, "That's the way it is, the display is in spec, and you'll have to deal with it." I could hook the DVI cable up bypassing the switch, but that makes every switch from the Mac to or from my other computers a two-step process that takes my hands from the keyboard to fli p the source switch on the display, which is the kind of thing that will dr ive me batty. Here's the chart of experiments: My mini -> original DVI-VGA -> my Samsung VGA cable -> my Samsung (VGA) = dark My mini -> my Samsung DVI cable -> my Samsung (DVI) = bright My G3 -> my Samsung VGA cable -> my Samsung (VGA) = bright My PC (Nvidia GeForce2 MX 440 card) -> my Samsung VGA cable -> my Samsung (VGA) = bright My laptop (Fujitsu P5020D)-> my Samsung VGA cable -> my Samsung (VGA) = bright Go to Apple Store, explain situation, Genius guy gives me a new DVI-VGA adapter. My mini -> new DVI-VGA -> my Samsung VGA cable -> my Samsung (VGA) = dark Go back to Apple Store, this time bring mini and my Samsung to demo the issue. My mini -> new DVI-VGA -> their VGA cable -> their AOC LCD (VGA) = dark (judgment call, but it seemed dark to me) Their mini -> new DVI-VGA -> my Samsung VGA cable -> my Samsung (VGA) = dark Their mini -> my Samsung DVI cable -> my Samsung (DVI) = bright What we didn't do that looking back we should have, is hook my laptop to their VGA LCD and show how bright it would be compared to the minis. I'm assuming here, but given the evidence, I think it's a valid one. Apple's pushing the mini as a part of a two-computer solution using a KVM switch, but I can't recommend this to my clients given what I now know ab out the mini's VGA output quality. Joined: Feb, 2005 Posts: 4 Hello, Same problem but slightly different. May help My 142 Mini is hooked to a CRT VGA Formac 21/380 monitor. No signal, unless I rock the DVI adapter in the mini, slightly away on th e right side (seen from above and front). It seems that the pins on that side (the digital pins) need to have no contact, but contact needs to b e good on the left side (the analog one). When I find the right position my monitor is OK, bright and perfect and s tays like this for a long time, even between shutdowns. Ther seems to be a problem on the DVI side on the mini (rig ht from above and front) Any DVI plug engineer ? Which ones safely n RE: Mac mini VGA output very dark... Joined: Feb, 2005 Posts: 32 Wow - I wouldn't cut pins, even if I knew which ones. You might want upgrade monitors in a year or two and want to use DVI. If those pins are the problem, better to find/make a DVI-VGA adapter that ignores them - doesn't even have contacts for them. prod_id=1209 So, I guess it is possible to convert the DVI-D signal to VGA - This isn' t just passing the already included VGA signal from the DVI port, but is actually generating new VGA signal from the Digital signals. I'm sure if mass produced, this price could be brought down to somet hing more palatable. Joined: Feb, 2005 Posts: 4 Thanks Casper I would cut pins on a DVI-VGA adapter, not on the mini, not on the cable. I think that different brands of adapters have different cabling schemes, and I can't find any clearly described... Joined: Feb, 2005 Posts: 4 Hello, It worked (for me) I cut some pins from my adapter (DVI male plug) Now I can fix it firmly and I get a bright signal I cut pins number 3,4,5,9,10,11,12,13,19,20,21,22 So my adapter is using only analog pins + grounds It semms, for my old CRT, that there was a conflict with some of these pi ns. Hope it helps Georges I cut the pins with small tweezers :) n RE: Mac mini VGA output very dark... Joined: Jan, 2005 Posts: 42 I called Apple tech support one last time. He also said he didn't think my problem would be fixed by sending it in b ecause the new one would have the same issues. I asked him if Apple had any plans to make engineering changes to the motherboard to fix this pro blem and he said NO. He kept referring to my problem as "incompatible wi th third party monitor", implying that my equipment was at fault. I only ordered from the choices on Apple's website - memory, Superdr ive, etc. In summary - they won't fix it and they won't take it back. Joined: Feb, 2005 Posts: 27 I now also have decided to call Apple tomorrow and return my Mi ni. My support case is open for more than 3 weeks now and until now I di dn't get any information on - whether they plan to fix the problem, - when they plan to fix the problem, - how they possibly plan to fix the problem. I have reached a point where the answers to these question are no more important to me. I simply don't want to deal with a company that has an information policy like that. It is absolut not essential if the machine is built to order or not. It is faulty, they have t o take it back, there cannot be any discussion about that. Don't listen to any blabla about "thir d party monitors". This machine was advertised to work with third party monitors. The truth is that it generates non-standard video signals. Joined: Mar, 2005 Posts: 1 Ok, you guys are going to love this. So I've got a mini hooked up to an Apple Studio Display 17in. CRT with th e DVI to VGA adapter (since this monitor originally came with a VGA cabl e standard) Same dull video output that the rest of us are seeing. I've also duplicated the problem twice at my work with two minis and any of my Sony Trinitron displays. So the moral of the story is, that even a n Apple 17' CRT (which is still a rock solid monitor after a few years o f service) is not compatible with their own hardware. I was planning on switching my entire Editorial staff to minis. Fix the problem, Apple, or this IT Director will take his business elsewh ere! Is one of these a G5 PowerMac tower that has DVI output? Since I also hav e the dark image problem with my mini, I've been wondering whether the m ore expensive models with DVI output might have the same problem with VG A CRTs that cannot adjust to low signal voltage. Can anyone tell me what function (if any) should the digital pins have in this adapter?.... I (from an uneducated non EE point of view) would hav e thought that these pins should never have been connected, and that rem oving them should have done nothing at all. Now if some of the DVI pins in the adapter are shorted/terminated incorre ctly , this could be causing the power output on the VGA to be pulled do wn, and causing the Dim video (or in your case) there to be no picture. Ie, Try rocking the DV I adapter slightly away from the Mac Mini's DVI port on the right side, so, the Analogue pins are pushed in, yet the digital pins are not.... I too had some major issues with my Samsung SyncMaster 172N when my Mac Mini arrived. Using Apple's DVI to VGA adapter, the display rarely showed anything. Eve n when the Mini would display the desktop for a brief moment and I could lower the display's resolution, it would flicker and go to a blank scre en. My solution was to toss Apple's video adapter into the trash and move to a FoxConn DVI to VGA adapter altogether. Upon making the switch, my disp lay worked immediately, and it wasn't even close to being as dark as it was when Apple's adapte... |
| www.xlr8yourmac.com/feedback/mac_mini_dim_video.html Ct magazine (print version) tests, the analog video output level was be low 530mV (below VESA standards) See bottom of page for links to other M ac Mini related articles and docs. He said he solved this b y trimming the pins on the adapter's dvi side resulting in a good conne ction of the analog vga pins and better video quality. Perhaps if this is the root of the dark video problem then all that is n eeded is a slight adjustment to the positioning of the dvi connector on the back of the mini to make it easier to seat the pins on the vga sid e.. I run it at 1124x768 @ 75 Hz Running it at @ 85 also works, but then the the image start flickering when I activate the 'light-frame' option of this monitor (enhances bri ghtness and/or contrast) Of course I have calibrated the monitor in OS X and the brightness is no w set at 27 (on a scale from 0 to 100). Regards, Armand" Some mentioned they had (not all noted it helped) but some monitors may b e more prone to the problem (assuming the Ct magazine test results on vi deo level is common). I am very happy with the r esults since it replaces a g3 beige tower that was upgraded to g4-500/4 0/768 with a 120 raid 0 I also hung a lacie 160 external firewire off the back of the mini and xbench summary scores went from 121 to 136 whe n I booted from the firewire drive.... I have a HP 23 inch L2335 display that definitely has the low brightness problem with the Mini. My Windows computer is much brighter, sharper in comparison. If I didn't have the Windows computer to compare, I might not have noti ced as easily to be honest and just cranked up the brightness control. It's like thinking DVD video lo oks okay until you see HDTV video. Maybe you guys could start a new topic on the Mini and ask people about the other problem that seems like a bigger deal to me. Why isn't the Mi ni fully compatible with single link (up to 1920x1200) DVI monitors. My L2335 has DVI and works great with my Powerbook G4 at 1920x1200. With the Mini I get colorful static in black scene space like others here ar e writing about under may different resolution options. I brought my Mini to an Apple store and plugged it into one of their 23 inch DVI displays and it worked fine. It sounds like an ATI/Apple software problem to me with the DVI connect ion. The Apple website has this specification about the Mini: "supports coherent digital displays up to 154MHz; supports non-coherent d igital displays up to 135MHz" That's the first time I've seen this. It it just referring that it doesn 't support higher resolution (dual link type) displays like the 30 inch ? Thanks, Dave M " (added 2/24/2005) "I was about to post about this on my blog, but I'm glad you're databasi ng this apparently widespread issue. The 6600GT is hands down far brighter and higher contrast. And knowing the Mini sports an in tegrated version of the Radeon 9200, I couldn't say I was too surprised by that; however, my girlfriend's computer which I had built for her ove r a year ago uses a Radeon 9200 SE that is distinctly more contrasted vi a an analog VGA cable into a Samsung Syncmaster 198n (purchased while sh e was visiting family in Korea). I'll try out DVI tonight - though it's unfortunate that VGA folks are out of luck. I'll admit that though the Mini outputs far darker and less sa turated than the 6600GT, it's not unusable. I've watched several xvid vi deos on it - though I do usually keep my room pretty dark when I play vi deo. The mini produces a bright, sharp image on a Dell LCD with DVI input. Th e Mitsubishi monitor produces a bright, sharp image when driven by a VG A signal from a PC with a Radeon 8500 video card. Chris C " (added 2/23/2005) "I am experiencing the exact same problem as encountered by others. Mini > DVI-VGA > Dell 1701FP LCD = Dim Mini > DVI > Dell 1701FP LCD = bright PC > DVI > Dell 1701FP LCD = bright PC > VGA > Dell 1701FP LCD = bright The dimness as measured by Gretag Macbeth Eye One Display calibrator is around 78-80 cd/m for the Mini > DVI-VGA (analog) connection, whereas t he other connections all measure reliably around 139-140 cd/m. When the Mini was connected via the DVI-VGA dongle and the PC was on the DVI in put, switching between the two inputs on the Dell was like night and da y Now, the Mini is hooked up to the DVI input on the Dell while the PC is using the VGA input BUT I have run into another problem - random static on dark backgrounds. Problem is worse at 75Hz refresh rate with static occuring frequently; setting the refresh rate to 60Hz improves matters , but static can still be seen when viewing dark pages. If the screen s aver kicks in, then the whole display gets really bad with red, green, blue and white dots flashing all over the screen. Will try to take a pi cture of the static and post later. tk " (added 2/23/2005) "I actually started that thread on the Apple Discussion board. I'm using a 21" Samsung 213T LCD and the difference between DVI and VGA is night and day - DVI is crisp, bright, and clean, and VGA is muddy and gray. The Samsung is perfectly fine with other VGA sources, including 3 or 4 P Cs, and my old Blue and White G3. I've tried other displays and DVI-VGA adapters with no joy. I'm more fortunate than many mini owners in that I _have_ a DVI input to use - i t's a pain but I can bypass the KVM and switch the source on the monito r, too. Bring your own display, keyboard an d mouse, indeed - as long as it's DVI! Running video from the Mini through the DVI-VGA adapter lo oks awful, regardless of whether it goes through a KVM switch or is hoo ked up directly to the monitor. Edges, especially on typographic characters are not sharp. I t is especially noticable when switching back and forth between a Windo ws PC and the Mini. It would be impossible to use this device for anyth ing important like Photoshop or even viewing DVD's. I borrowed a Dell 1704 LCD monitor and tried hooking it up both via the DVI connection and via the DVI-VGA adapter. In both cases, the video lo oks much better than on the glass monitor, but still not as good as the PC output. I also took it into an Apple store and tried it with one of their monitors (LCD), of course it looked good on their $1000 monitor. This would have been my first Mac The mac's are touted as being great f or design work and photo manipulation, etc. U nfortunately, the Mini is unsuitable for this purpose. I can't believe that during the development and QA process at Apple that they never tes ted it with any third party monitors. Steve Jobs said this device would work with any industry standard monitor. I'm going to try to return my Mini tomorro w to an Apple store. " (added 2/23/2005) "Mac mini connected to a Sony CPD-200ES CRT through VGA. Have tried both KVM and direct connection, no difference. While I do go through a KVM s witch, a direct connect yields no difference. The display is bright and "normal" when connected to my Windows machine. When my mini was connected to an Apple LCD (DVI/Digital-Mike) at the dea ler, the display was bright and vivid! Russ N " (added 2/23/2005) "Replying to macmini's used with vga I have mine hooked up to a vga LCD set to 1280x1024 and have no problems . Mac mini 142GHz BTO 512 MB (factory upgrade) 80GB HD Blue Tooth (turned off for now) No Airport card Wired Apple keyboard/mouse Daewoo F227B LCD 17" using cable that came with the monitor and the vga adapter that apple supplied with the mac mini. Display appeared slightly brighter on the G4 MDD Both were usable and text was crisp on both. By the way, it did not matter if I used the Mini or the MDD supplied VGA/DVI adapt er, the adapters did not seem to change the brightness of the mini. Mar k " Some monitors may show this more than others apparently. A t first the display was dim and "dull", but after playing around with t he refresh rates, I found that 75hz gives me a fairly bright and clear picture (but still not as good as my AMD W2k PC and Nvidia Gforce 5900 however). I find the display tolerable now, but in a direct comparison to the AMD box it is still not as bright or clear. I have emailed Apple about my c oncerns for future expandability, considering that there appear to be m... |