My desktop computer self-destructed last week (I'm posting this from a laptop) and I decided to replace it rather than try to fix it (it's 4.5 years old, and if I wait another year I'll be locked into Vista).
This new machine will have two disks (actually two RAID-1 pairs, but that fact should be transparent). My temptation is to put all system files on one disk (including installed software) and all user files on the other, so that I don't need to back up the system disk as frequently. However, I wonder if it makes sense to make an exception for sample libraries such as GPO, so that the associated disk traffic can be overlapped with system disk traffic.
If it matters, this machine will have 4GB of main memory, so I am hoping that the system's disk cache will reduce traffic anyway.
The best way to break down data is like this:
Disk 1: OS and programs
Disk 2: Audio / project files
Disk 3: Samples
If you are limited to 2 disks, then combine disks 2 and 3 by creating two partitions on a single disk, one for audio/project files the other partition for samples.
The amount of RAM does not help nor hinder disk I/O. The buffer size on the disks themselves and the size of the system cache does. The bigger the better in both cases.
Last of all, unless you are not planning to have a regular, reliable backup system RAID won't bring you much in the audio world. A waste of a drive in IMHO. For backup I highly recommend getting an external drive and using a good program to perform both DR (bootable) and backup recovery capabilities.
In the Mac world that would be Time Machine that just shipped with Leopard. It is *fantastic*. For Windows whatever program you like.
Hope this helps!
We are the music makers, we are the dreamers of dreams …
24" 2.4 Ghz iMac, OSX 10.4.10, MOTU 828 MKII, 2 Glyph 250 Gig external drives, Logic 9, Finale 2008 GPO, JABB, Strad, Gro, Reason 4, EWQL Storm Drum, Adrenaline, Symphonic Choirs, SO Gold,All Arturia Synths, Many NI Synths, Spectrasonics Synths, KH Strings, VEPro on a Windows 7 4x 2.8 Ghz 12 gig of RAM