That's a pretty interesting question...a question that I don't have an answer to, but I can make an educated guess.

If you are speaking purely about rendering your videos in PD7, the power of your CPU and amount and type of RAM are the crucial elements here. A Core 2 Duo CPU will be better in rendering than a Pent 4. A quad core will render better and faster than a Core 2 Duo. If you have DDR2 DRAM, this will help rendering times as well.

How much faster you want rendering times will differ according to your processor of course. I decided that a duo core cpu was slower than a quad, but that minimal savings in render time and the inability to overclock the quad cores effectively weren't worth it for me.

As far as playback from your hard drives, it seems RPM speed isn't as important as data rate per second, according to some. If you've got SATA drives, you'll be getting average transfer rates of around 168MB per second or more.

The basic way, and probably the simplest way of optimizing your system is to turn off all unnecessary programs in the background, defrag your disk drives, keep your registry clean, and remove all spyware from your system.

I'm not sure if placing your video sources, temp files, and program on different drives will help significantly speed up the rendering process. If anything, this approach may actually slow things down, (albeit in fractions of a second) since your computer must access different drives in order to access files. Some users on here report that their systems are more stable when they put all the clips and project resources onto one folder on one drive.

In any event, my guess is that the separation of your files to different drives will give you minimal increases in rendering efficiency at best, and not at all at worse.