i just ordered and setup a western digital velociraptor 10,000 rpm drive for all my audio samples and programs, its replacing my 7,200 rpm WD caviar. so far my performance is horrible. i moved everything over to the raptor, programs, samples, cache thinking that would be the best thing, ableton has been crashing and been having really bad latency. so i switched my projects back to the caviar and had a crash free session all night. that is with everything on the caviar. i don't get it. is there a setting or something i'm missing?
latency is a function of your soundcard and its drivers, not your drives.
The setup for your drives should be:
a) OS, apps and plugins on boot drive
b) Sample libraries on a second separate drive
c) audio projects and track on a third drive
(this give you best efficiency and lets all the programs and services run without interrupting the smooth flow of recording/playback data)
7200rpm dedicated drives can stream well over 100 simultaneous tracks, you should not need 10k drives (and in fact they do not provide that much more efficiency plus they are noisier)