What happened to 2GHz?
What a difference a few weeks can make - that's the first thought that comes to mind when discussing Intel's latest incarnation of the Pentium 4, now running at 1.8GHz. Back in April we expected the next Pentium 4 chip to launch at 2GHz, 1.8GHz and 1.6GHz CPUs had never been discussed, much less released to the public. That all changed however when rumors of their release first hit the web a few weeks ago. Intel officially confirmed the July release of both chips during last week's PC Expo forum in New York. In fact, shipments have already commenced to PC manufacturers; retail availability should be immediate.
Where did these processors come from, and why did Intel decide to release them just recently? Lets tackle the first question before tackling the current market conditions surrounding the Pentium 4.
Step on what?
With the release of the Pentium 4 1.7GHz, Intel introduced a new Pentium 4 stepping, C1. Unaware of what a processor stepping is? Think of the updated stepping of the processor core as a newer version. Much like a game developer releases a newer version of their latest game with all the latest bug fixes and performance enhancements, CPU manufacturers AMD and Intel release newer processor steppings every now and then.
1.80GHz of pure bliss
These new steppings can bring with them a number of bug fixes (processor manufacturers refer to hardware bugs as erratum), specification changes, or manufacturing changes in the processor core itself. For instance, the new C1 stepping of the Pentium 4 brought with it a specification change, the core voltage was increased from 1.7V to 1.75V. Back in April AMD Athlon users were overjoyed at the overclocking gains witnessed by Athlon's AXIA stepping. Manufacturing improvements implemented in AXIA chips (and their close AVIA/AZIA cousins) gave the Athlon core more headroom; previous steppings topped out around 1200-1300MHz. Since this new stepping was implemented on all Athlon processors in production, 1GHz chips could hit speeds of over 1.4GHz in the hands of a skilled overclocker with the right motherboard.
Unfortunately, C1 doesn't appear to have brought with it a substantial overclocking boost, our original B2 stepping Pentium 4 1.5GHz could easily hit 1.7GHz, but it does scale high enough to allow Intel to manufacture sufficient yields of 1.8GHz processors to supply the market. In the case of both processors we're simply looking at new multipliers, 16.0x for the Pentium 4 1.6GHz, and 18.0x for the Pentium 4 1.8GHz. As always, we'll discuss how well our 1.8GHz chip scaled in the overclocking portion of our tests, we struggled mightily to overclock the P4 1.8GHz higher than our 1.7GHz chip. Eventually it succumbed to our will.