To clarify, this is a matter of diminishing returns. The OP has quite simply one of the best processors on the market right now (bar a few), and his GPU is pretty close (all I can find is that it's somewhere in the 5800 series). It's true that his GPU was stressing more than his CPU, but below a threshold of about 2.8GHz (I'll admit this is an educated estimate) on the CPU, no matter how much you crank your GPU, it's not going to make any difference at all. I wrote that in the hopes of preventing people from seeing all of the "Go buy a better GPU" posts and then being mistified when their 1.6GHz computer still isn't fast enough to play the game. It seems like common sense to some of us, but to others, it's not so much.
To site a specific example, the entire discussion about mortalabattoir's slow GTX230. Now the 230 is certainly getting up there in age as far as GPUs go, and it was never designed to be the workhorse the 280 and beyond were, but I would argue that it's much more probable that his <1000 score probably comes from his 2.66GHz processor more than his GTX230. The 230 isn't helping, but if he OCed that CPU up to 3.0+, he'd probably see a marked difference without spending a cent. If he want's to see 2k+ numbers, he's probably going to be wanting to get a new GPU, but I should think bumping up his CPU would be more than enough to net him another 1k on this Benchmark.
(on a related note, I stand by my original assessment, however, my GPU usage readings may well be modified by the fact that my CPU may well be bottlenecking it a bit. However, as I received well above average marks on the low-def ratings, and average marks on hi-def, it should be enough to help get people with to-low-to-use scores on the right track)
This got me thinking and I was bored, so I ran the benchmark at a couple of different CPU speeds to simulate low end setups. The tests are low res only (no need testing high with this GPU) Keep in mind that I'm not isolating the CPU entirely, I'm also changing the bus speed.
C2D e7200 @ 2.0, 2.5, 3.0
It seems that even a meager 9600GT is not GPU bound with a C2D until somewhere around 3Ghz. I'll try tomorrow at 3.5, but I've never taken this chip that far (stock voltage only at this point :) ).
Added a C2Q@3.2 and O/C'ed the 9600GT to 725/1815/1000, and my score jumped to 2740 at low res. I'm pleased; it looks like I'll be able to hold off on purchasing a new GPU for a bit. Edited, Jul 25th 2010 1:28pm by Pickins