In Dxdiag, my processor is called an Unknown Intel P6 Processor. Can this hurt performance (ie, is it not recognizing CPU enhancements like SSE3?)

That's actually quite interesting. While the Core 2 does have some Pentium Pro (P6) blood flowing through its veins, I wouldn't have thought that it would be classified as a P6 chip by non-Core-aware versions of Windows/DX.

Anyway, here's a To-Do list:

-Make sure you have the latest version of DirectX installed. For WinXP, you want DX 9.0C. I believe that it is the DirectX component of Windows that allows you to take advantage of CPU extensions such as SSE in 3D applications.

-Make sure that your installation of Windows is fully updated.

-Install the latest drivers for your motherboard's chipset

-I'm no expert on newer Intel CPUs, but you may need this CPU identification utility from Intel.

There once was an Opty that lived in a shoe...nevermind.
S939 Opty 185 @ 3.2GHz
4GB PC3200
TWO GTS-640s BIOS-flashed to 625/1458/1950
Blu-Ray/HD-DVD Combo
750GB and X-Fi

Have you tried using CPU-Z

C2D Quad Q6600 @"soon OC"
1:1 Ram : CPU
4gb Elipedia @ 850mhz
EVGA 680i
BFG 8800 GTS 512mb - in post!
680w Thermaltake Purepower
2 x 250gb Sata2
Vista Home Premium 32bit
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