Behind The Silicon Curtain: Exclusive Test Of The P4/2666 With 533 MHz Rambus

Conclusion: Top Performance, But Only With 533 MHz

As of today, we have already tested the processors that Intel won’t be bringing you until the fall of this year, at the earliest. Above all, this is related to the models Pentium 4/2666 and Pentium 4/2533, which are the first CPUs to offer support for 533 MHz Rambus. Our benchmark results clearly prove that if Intel changes the FSB and memory clocks (to 133 MHz and 533 MHz, respectively), this will put it quite a distance ahead of its competition from AMD, as well as its own series of processors. In the Office Performance category, the Pentium 4/2666 with 533 MHz RDRAM soars about 50% above the fastest AMD Athlon XP 2000+ (VIA KT333 platform and DDR333). In MPEG-2 video encoding, the Pentium 4/2666 is approximately 25% ahead of the AMD Athlon XP 2000+ (VIA KT333 platform). What’s more, the P4 2666/533 achieves higher benchmark results than a P4 3000/400 in some categories.

Here, we’d like to make a general observation about the benchmark tests : used together with a 533 MHz memory clock, the performance of the Pentium 4 increases accordingly in all categories. By comparison, the growth in performance for the AMD processors, in conjunction with the VIA KT333 chipset, is relatively small. This fact is partially due to the DDR333 memory modules that we used, which did not work in CL2.0 mode. So, now it can already be determined that, in the future, AMD processors (Athlon XP/MP) will not make such big leaps in performance based on an increase in core clock speed alone.

Our detailed tests show that forthcoming P4 CPUs with 133 MHz FSB clock used in conjunction with the 845E chipset (DDR SDRAM support) will effectively be castrated. This is because the Pentium 4 has a problem : the increase in clock speed (e.g. P4/2533 or P4/2666) will be rendered useless by the slow DDR SDRAM memory bus of the 845 platform. In the mass market, the 845 chipset dominates by nearly 100% - and this will remain the case for the next six months. But only 533 MHz RDRAM enables the processor to attain high performance. Eventually, the dual-channel DDR solution will receive some sort of technological boost, however there’s still no sign of development in this area. And one shouldn’t forget that even a dual DDR platform for P4 should be priced at a level that is similar to a Rambus system, considering that it’s from Intel.

Intel is facing a difficult situation with Rambus, and the errors of the past lie heavy on the heart. The concept of technology franchising cannot be brought to fruition without controlling the production. The power lies in the hands of memory manufacturers such as Samsung, Corsair or Viking. As a final comment, please note that, currently, Rambus and DDR SDRAM are equally priced.