SCSI - FTW.
I use 36gb 15k scsi drives, and i tell you what. The speed is tremendous.
SATA ide, does not matter. the Physical restrictions of the drive prevent the hughe performance difference.
7200 rpm drives, IE it doest not go any faster than that
10k makes for huge improvement
15k well that is 2x the sata / ide.
Now with cache on the drives, 16mb, that is cool, but you hardly work with any data now adays with that amount or lower.
IE battle field 2, still needs to load the map, etc....
Scsi has the advantage of having, (with the right controller), a Intel, IO processor, that offloads from the CPU, to the CARD cpu. i use a $100 raid card off of ebay, a u320 w\ 128mb ram on a pci-x slot. Litteraly destroys anything.
Disks are funny, people brag about having 80mbs transfer rate. WELL that is good on paper, but if you have 1 drive, and you are copying 800mb file, from 1 directory to another, then you cut that in half, and add cpu overhead. the raid controller on most mother boards utilizes soft raid. Meaning that there is no processor onboard, to preform the disk io, so it uses a small slice of cpu processing. myself, i saturate my 320 MBs buss, easily, but i use files in the 20-60GB size all the time, hence my profile machine in my sig..
For a ultimate gaming machine, 15k cheetahs, x2 in a striped array, simply blow away many of the hard drives avaliable. Dont get started on 3-4 drive arrays. It is RARE that i am ever the second person loaded on ANY map in BF2. i am usually in a tank, or helo, ON THE WAY, before the 2nd or 3rd person even loads in. and i dont have a MEGA game machine, ---yet...
It is all about SPEED when it cmoes to drives. i rather have 14- 9gb 15k drives, as my main os drive, than 1-300 gb sata.. Simple math, more spindles=faster transfer rate. more spindles=Much higher Disk I/o which = faster to preform a specific function, and release disk to preform next job.