Here is a summary of the best-playable settings for each of the video card configurations. This should hopefully help you to decipher the graphs with a little more ease.

We have also added in the results for a single GeForce 6800 GT from part two and part three, to give you an idea of how well a single GeForce 6800 GT performs with a slower CPU.

On one hand, as we've just found out, SLI can be affected by the speed of your system's processor in certain titles, but not all. On the other hand, a single-card 6800GT is almost never CPU-limited.