It doesn\'t really matter where you put Gigastudio itself, since it is loaded into memory once and stays there until you quit the program. So one HD for Windows+sequencer+Gigastudio and then one or more for the samples is fine.
1. As someone wrote in another topic here on the forum, putting your samples on different HD\'s on different IDE channels (or SCSI) can increase performance. One idea I\'ll try is to put all the really big samples on one HD and the rest on another and see how it fares.
2. Uhm well. There\'re a lot of factors there. CPU speed, the faster the better of course. The chipset. VIA has slower memory access than Intel - so it seems on my current VIA chipset (and reviews indicate it too). The HD access time is important for Giga, since it is constantly moving about on the HD retrieving small packets of data.
The amount of RAM only really matters when you get to the point where you have no RAM left. Or when you have less than 128MB and want to play with the big piano samples and such.