Introduction

Whenever a next-generation GPU such as NVIDIA’s brand new GeForce 8800 line is launched, media outlets such as ourselves always test with the fastest processor we can get our hands on so that we can accurately gauge the full performance potential of the new hardware. As you saw in our GeForce 8800 GTS/GTX Performance Preview, NVIDIA’s latest GPUs are capable of delivering performance numbers over two times faster than the previous generation in games like Dark Messiah of Might and Magic and Oblivion thanks to NVIDIA’s new G80 architecture.

NVIDIA has incorporated new features such as a unified shader architecture with up to 128 stream processors in the GeForce 8800 GTX, which also has a 384-bit memory interface running at 900MHz with 768MB of memory. This pales in comparison to the GeForce 7900 GTX, which featured 24 pixel shaders and 8 vertex shaders, as well as a narrower 256-bit memory interface.

With so much graphics horsepower onboard GeForce 8800 however, some potential 8800 card owners may run into cases where the card isn’t running to its full potential and won’t see these huge performance scaling increases, the card isn’t able to “stretch its legs” so to speak. This can occur frequently in games that are based on aging game engines. Sports titles for instance are often based on the same rehashed game engine year after year. In some cases, performance can even be held back due to a game that’s poorly coded.

But software isn’t the only aspect that can hold back a next-gen card at launch, another culprit is often the CPU.

Quite simply, with next-gen graphics processors delivering 1.5-2X times more performance than their predecessors at launch, the CPU can become a bottleneck in many titles we test with. After all, the clock speed of new CPUs tends to only increase in increments of 100-200MHz; only delivering about 10% more performance with each new processor release. You can see this in benchmarks where you hit the same frame rate regardless of graphics settings (such as increasing screen resolution from 1280x1024 to 1600x1200). As soon as a faster CPU is inserted, your frame rates increase.

This is a situation you’d like to avoid if you’ve just plunked down $700 on a brand new 8800 GTX graphics card, as you’re not getting the most from your money (although being CPU-limited does allow you to crank up the image quality settings for “free”, as you won’t get the performance hit usually associated with these setting changes).

Intel’s latest Core 2 CPUs are based on an entirely new micro-architecture, with a wider execution core, 1,066MHz FSB and unified L2 cache architecture with up to 4MB on-chip. As a result, Core 2 delivers substantially more performance than any previous processor from AMD or Intel, including AMD’s flagship Athlon 64 FX-62.

This makes the Core 2 Extreme X6800 we tested with in our GeForce 8800 Performance Preview article an excellent companion for NVIDIA’s latest GeForce cards, but what about the millions of AMD users out there? Is the GeForce 8800 GTX still capable of outrunning the Radeon X1950 XTX by a factor of 2X on an Athlon 64 X2 4200+? What about the 5000+?

Many of you have asked us this very question, and today we’re here to provide some answers. We’ve included AMD CPUs ranging from the Athlon 64 X2 3800+ all the way up to the Athlon 64 FX-62 to see how the GeForce 8800 GTX and 8800 GTS, as well as ATI’s Radeon X1950 XTX scale with these CPUs…