Okay, here is the best advice I can give you about HD's. Did you read my PCI SATA card
articles. First I would say especially since you will be doing video you need a good set of
hds. Trust me, this setup is proven. Your main drive can be kept on ata66. Only put your OS and apps on it. A seritek sata raid 0 is the way to go for the next drive. You can
get this card and 2 sata drive for less than two hundred bucks. It will be about 3-4 times
faster than your standard drive. This is used for scratch disk and storage. Think of ata 33
as a straw, ata 66 as a hose and ata 100 as a pvc pipe- a sata raid 0 is a drainage pipe. Now think of data as water. This water must go back and forth and both ways at the same time. I would not go less than the pvc pipe. Anyway, the sata cables are small and make
case airflow better. Besides when you upgrade to a g5 you will still be able to use them.

"Hard drives are the biggest bottle necks in a computer system."