First of all I would like to say that Intel improved the performance of its dual-core solution quite significantly. Thanks to the finer 65nm production technology, Intel increased the clock frequency of its new CPU and equipped it with the larger L2 cache. As a result, Pentium Extreme Edition 955 is not an eternal loser in the dual-core duel anymore. There are a lot of applications where Pentium Extreme Edition 955 managed to defeat AMD Athlon 64 X2 4800+, the top dual-core solution from Intel’s competitor. In fact, AMD processor remains the leader only in gaming applications, in professional OpenGL tasks and a few codecs. However, Athlon 64 X2 4800+ cannot be called a fully-fledged rival to Pentium Extreme Edition 955, because in about two weeks from now AMD will launch its new faster dual-core Athlon 64 FX-60 processor. Then we will talk again about the today’s fastest dual-core solutions.Besides higher performance, the new Presler core of the dual-core Intel CPUs can also boast very high overclocking potential. We managed to reach 4.26GHz clock speed on Pentium Extreme Edition 955 easily without any additional cooling involved. And the experiments carried out by some hardware enthusiasts proved that even 5.5GHz is not the maximum for the new Intel Pentium Extreme Edition 955 on the Presler core. So, you can speed it up quite tangibly by simply overclocking to higher frequency.However, we shouldn’t also disregard some drawbacks of the NetBurst architecture, which remained even after the transition to 65nm process. I am talking about high heat dissipation and power consumption of the new Presler based processors. Although more advanced production technology allowed to bring these parameters down a little bit, they still remained as high as those for the top-end single-core Prescott based CPUs. The typical heat dissipation of the new Pentium Extreme Edition 955 is even set at 130W by default.In conclusion I would like to say that the major advantage of the Presler CPU for the manufacturer is its internal core structure composed of two individual dies. As a result, Intel managed to significantly reduce the production cost for these processors, which will help inexpensive dual-core Pentium D processors invade the market in 2006.
This setup gets too hot under load on our open test bench—with CPU temps up to 90 degrees Celsius—causing the CPU to resort to thermal throttling in order to cool itself. Of course, once we found this problem, we had to throw out all of our benchmark results, because they would be invalidated by the presence of TM1 throttling, which can really hamper CPU performance.Having spent a number of hours troubleshooting this issue, I don't think it's straightforwardly caused by a CPU that runs too hot. In fact, we found the problem to be worse on the same Intel 975X-based motherboard with an older Extreme Edition 840 processor that we know to be sufficiently cooled on a different motherboard using the exact same cooler. The problem appears to be caused by the way the Intel 975X mobo is reading and reacting to thermal data from the CPU and thus controlling the fan speed of the stock Intel CPU cooler, although these things get complex enough that I hesitate to pinpoint an exact cause. We are on our second CPU/mobo/cooler combination without a resolution. Intel says it is still working on a fix, and all I know is that this issue doesn’t look to be something that can be resolved by a simple BIOS update.What I can tell you is that the throttling problems were easily resolved once I purchased one of these babies, a Zalman CNPS9500 LED cooler, and installed it on the system. With the thermal problems out of the way, I can proceed with CPU testing, so we should have a review for you later in the week or early next week. In the meantime, you may want to watch the reviews elsewhere on the web today carefully to see that they address any possible thermal problems and thus have been sure to produce valid benchmark results.
