Win 2000 & XP (in particular, I know not about other OS's) takes advantage of swap file space split between two drives: because Win, when it DOES use swap (virtual memory plus a few other things) space tends to request multiple simultaneous read & write operations: even on a SCSI drive there can be traffic jams: one operation must wait for the disk head to finish the last operation. Because the hard disks (even your beauties) are far, far slower than main memory, this can bog the system down, particularly with large (e.g. photo images) chunks of data, which overflow the disk cache and, breifly, flood the disk, BUT NOT THE SCSI BUS; so splitting up the SWAP file makes more efficient use of the fantastic SCSI 160 MB/s bus.
One question 8 GB + 5 GB - 18 GB leaves you with a 7 GB partition which purpose you don't list. Also, I may be mistaken but I believe because SWAP space re-builds (and erases) after each operation it is not particularly useful to dedicate a partition to it?
If so, you'd be better just storing files (tiffs, etc.) on an un-partitioned 36 drive (say logical G), giving your apps a bit more room (say 12 GB of the 18 drive (say logical F)) and loading the OS in the remaining 6 GB (C:) of the 18, and telling Win to use C and G for swapping.
Bloody long post. Sorry.
Schiller: "Against human stupidity even the gods contend in vain"
Nietzsche: "Against BOREDOM even the gods content in vain"