Verdict: In performance terms it's no slouch, but then again a 3.2GHz Pentium 4 is pretty nippy anyway
The Intel Pentium 4 family has just got a surprise new sibling: the Pentium 4 Extreme Edition (EE). Boasting the same Hyper-Threading technology and running at the same 3.2GHz clock speed of the current top-end Pentium 4, this new processor differs from the rest of the family in one major respect. Intel has added a huge 2MB of Level 3 cache to the chip, in addition to the 512KB of Level 2 cache included with a standard Pentium 4. This might be an interesting new addition to the Pentium 4 family, but the hardware community has been quick to spot that a processor with 2.5MB of on-chip cache is not exactly breaking new ground for Intel. Xeon MP chips feature exactly that, and on closer inspection, the EE has another similarity with Intel's high-end 32-bit server processor. The handy WCPUID utility (www.h-oda.com) identifies the EE as an M0 stepping processor - the same as a Gallatin core Xeon MP.
While the EE might share the same stepping and cache configuration of a Xeon MP, the Xeon MP is a 603-pin chip and the EE is a standard Socket 478 design. Also, the Xeon MP's FSB is limited to 400MHz - considerably slower than the EE's 800MHz. Essentially, the chip is a Frankenstein-esque creation. It appears to be a Xeon MP that was subject to some quick, dark science in one of Intel's labs to create a top-of-the-range performance processor compatible with existing P4 motherboards. Given the excellent performance of AMD's recently launched Athlon 64 FX-51 processor, it's perhaps not surprising that Intel felt the need to respond.
Despite Intel's desire to make sure that the Athlon 64 FX-51's reign at the top of the processor kingdom is as short as possible, Intel is still being cautious about announcing a firm release date and price for the CPU. Adding 2MB of on-chip cache isn't cheap, so it's unlikely to cost less than £500. Still, it's equally unlikely that the EE will take its pricing cues from the Xeon MP - a quick Web search reveals a 2MB Xeon MP running at 2GHz will set you back around £3,000.
We fitted our Extreme Edition chip to an Asus P4P800 Deluxe - an 800MHz front-side bus board based around the Intel 865PE chipset. We then built a PC using the same kit that we used last month to benchmark the Athlon 64 FX-51: a Western Digital WD1200JB hard disk, Samsung SM-348 DVD CD/RW drive, Nvidia GeForce FX 5900 Ultra graphics and 1GB of Corsair XMS 3500 RAM.
As we expected, the additional Level 3 cache gives a slight performance benefit to some real world applications. However, the only situations where an EE will be faster than a standard Pentium 4 is when you're using large datasets. This is shown by the increase in performance in the image manipulation and video encoding benchmarks. Games will also run slightly faster, but we measured a mere 1fps increase in Wolfenstein: Enemy Territory. Compared with an Athlon 64 FX-51, the EE is faster at video encoding but not nearly as good at image manipulation. Nevertheless, both chips achieved an identical overall score of 1.75 so the EE is certainly a force to be reckoned with. We then overclocked the chip by upping the multiplier (Intel engineering samples ship unlocked) from 16 to 18 and boasting the frequency from 3.2 to 3.6GHz. At this speed the EE screamed past the competition in all but image manipulation, where the Athlon FX-51 was still slightly faster, no doubt due to its integrated memory controller.
CONCLUSION
Without a confirmed shipping price it's hard to make a final judgement about the Pentium 4 Extreme Edition. Certainly in performance terms it's no slouch, but then again a 3.2GHz Pentium 4 is pretty nippy anyway. If Intel really does intend in creating a new brand of CPUs aimed specifically at the enthusiast market then the company really needs to make the next Extreme Edition more extreme. As it stands, it's a fast but not groundbreaking chip that bears a suspicious resemblance to a Xeon MP.
