Introduction

While Intel’s official launch day for Core 2 is still a few weeks away, already Intel’s latest CPU is turning lots of heads. The performance delivered by Intel’s newest processor is simply groundbreaking. In our Core 2 Extreme/Core 2 Duo Performance article, we put two of Intel’s fastest Core 2 parts, the Core 2 Extreme X6800 and Core 2 Duo E6700 through the ringer. We ran our usual mixture of audio/video encoding tests, as well as OpenGL rendering with 3D Studio Max and Cinebench, and finished things off with both single-GPU and dual-GPU Radeon X1900 XTX CrossFire tests at 800x600, 1600x1200, 1600x1200 with 4xAA/8xAF, and finally 2048x1536 with 4xAA/8xAF.

In our testing we found that Intel’s new processors had no problem outperforming AMD’s flagship Athlon 64 FX-62, in some cases by percentages as high as 28% at 1600x1200 in gaming, while DivX conversion was almost two minutes faster for the Core 2 Extreme X6800 versus Athlon 64 FX-62. If you didn’t see our Core 2 performance article, you’ll definitely want to check it out if only to see how well single card and dual-GPU CrossFire configurations scale across a variety of resolutions.

ASUS P5W DH Deluxe system running CrossFire

Single X1900 XTX tested

But as promising as those performance results were, what if we were to tell you that those numbers were only a baseline, and that with a little bit of tweaking, a Core 2 system can run even faster than the benchmarks we presented you with on Friday? Guess what folks, it’s not only possible, we’re going to show you how and what kind of performance results you can expect as a result in today’s article!

Quest for more performance issue 1: the memory

The number one issue holding back the performance of the Core 2 systems we tested last week was without a doubt the memory subsystem, more particularly, when it comes to system memory.

As we’ve seen in the past with previous Intel processors, they tend to be very hungry when it comes to memory bandwidth. Therefore we were a little surprised when Intel decided not to provide official support for DDR2-800 in their high-end 975X chipset, as AMD has done with their new AM2 Socket Athlon 64 processors. Instead 975X is officially limited to DDR2-667. Intel’s newer P965 chipset supports DDR2-800, but it’s considered to be Intel’s chipset for the mainstream market and therefore lacks support for high-end features like ATI’s CrossFire dual-GPU technology.

We’re not exactly sure why Intel decided not to provide an updated version of 975X with DDR2-800 support. Our guess is that since an official 800MHz spec hasn’t been ratified by JEDEC they didn’t want to roll out another new chipset, but since motherboard manufacturers and even Intel themselves had to redo their own 975X motherboards earlier this year in order to support Core 2 anyway we think it would have been a perfect opportunity to add DDR2-800 support to 975X.

In other words, this means that the numbers we presented you with on Friday were with a Core 2 system running at the DDR2 memory speed of 667MHz, even though we were running memory modules perfectly capable of faster speeds.

The number one area we knew we could improve performance would be to run the DDR2 system memory at faster frequencies. We didn’t want to stop at 800MHz however, instead we were shooting for 1,066MHz! The following chart illustrates why 1,066MHz memory for Core 2 would be ideal: more bandwidth.

DDR2 Peak Memory Bandwidth
Memory	Peak Bandwidth
DDR2-533	8.5
DDR2-667	10.6
DDR2-800	12.8
DDR2-1066	17

With DDR2-1066 providing over 6GB/sec of additional bandwidth over DDR2-667, that should be more than enough to keep Core 2 and its 1,066MHz bus fed with data. In order to hit that kind of speed though, you’re going to need the right kind of memory. That’s why we decided to go with Cosair’s TWIN2X2048-6400 memory modules. To the best of our knowledge, these are the only DDR2 modules currently available on the market that provide CAS3 latency and fast memory timings at 800MHz. We wanted to test how latency affects performance, so this made the Corsair modules the perfect choice, plus we’ve heard reports that these modules are pretty good at hitting speeds of 1,066MHz as long as you aren’t too aggressive with the timings.

Pretty ornate down there huh?

Another shot of the system running CrossFire

Now that we’ve got the right memory modules, we need a motherboard that’s going to take us to the right memory speeds. This brings us to issue #2: motherboards.