I used to put the page file, and ALL temporary directories (including Cakewalk audio and pic, Moz, etc) on a separate drive. First time I did this the performance improvement was dramatic. Over the years the improvement has become less and less noticeable as both the memory management function in Windows, and the hardware have improved.
A week or two ago I finally built a Windows 7 machine for the studio, there is no discernible difference between leaving temp directories and swap space on the main drive and placing them on a separate drive. The good news is that it did not make matters worse, I guess<G>! I still use a fixed size swap file, but largely for superstitious reasons these days. It can't - that I'm aware - hurt things.