gamespot.com/gshw/stories/flat/0,12880,2781969,00.html
Both companies have successively introduced faster variations of their processors with the hope of claiming the performance title once definitively held by Intel. The Pentium 4 has decisively pushed the megahertz edge over to Intel, but in processors, speed and power aren't necessarily the same. However, speed increases are just one of the changes Intel has in store for the Pentium 4. Fortunately for those put off by expensive Pentium 4 motherboards and memory, Intel will introduce a new chipset, the i845, later this year that will support standard PC133 memory. Prospective buyers should also keep in mind that Intel is planning to move the Pentium 4 to a new socket interface later this year. That is to say, the 423-pin motherboard connector that the current Pentium 4 plugs into will be incompatible with future Pentium 4 processors. Consequently, if the ability to upgrade your processor is of importance, hold off on a Pentium 4 purchase, at least until the Socket 478 is introduced. The Pentium 4's architecture is a significant departure from the Pentium III and Athlon, which in turn makes it difficult to directly compare its speeds with other designs. All Pentium 4 processors have a 20-stage pipeline--twice the depth of the Pentium III. Breaking the processing pipeline into so many stages has made it easier for Intel to increase clock speeds, but there are some consequences. A longer pipeline raises the stakes when it comes to the gambling that modern processors do, that is, predicting the results of one operation in order to get a jumpstart on the next. Prediction helps keep the processor running at full speed and is based on a history of results for similar operations. When mispredictions occur, the Pentium 4's entire 20-stage pipeline has to be flushed to get back on track. The Pentium 4's trace-cache and double-speed arithmetic units help combat this penalty. Also, to ensure that the processor is never starved for data, the front-side bus has been accelerated to the equivalent of 400MHz, compared to 133MHz in most Pentium III systems. We'll look at the performance that the Pentium 4 is capable of shortly, but first we'll look at the price. Editor's Note: You can find comparative pricing on Pentium 4 processors in our 41 CPU Price Guide, which is updated daily from ComputerShopper's database of online merchants.
|