I ran a couple of tests to show why RAM speed is so important. Tests were done with Corsair 6400C3.
The first test was run at 3842MHz with 1:1 ratio. Memory speed was 427MHz (3-3-3 timings). Second test was done at 3564MHz with 2:3 ratio and memory speed at 594MHz (4-4-3 timings). I think the results speak for themselves.
3842MHz 1:1 DDR2-854
http://img263.imageshack.us/img263/8544/8mx23842me8.jpg
3564MHz 2:3 DDR2-1188
http://img263.imageshack.us/img263/4...2356323tb1.jpg
I think people have this misconception that CPU speed is the only thing that matters. But even if your CPU is not great, you can still get decent results if you have good RAM and know how to use ratios.