SATA2 VS Raptor VS RAID0

raptor +raid0 is the fastest combination you can get, but i still would use raid1
if you really have the cash to waste, you can always go with scsi 15k rpm disks on raid1 ;)

if you want to stick with home pc stuff, get a real bootable sata raid card such as 3ware
and plug in 2 raptor disks.

if you want to further optimize, get another card and place it on a an unshared bus. then add another
pair of disks.

now since you have two raid cards with one sets of disks, you can configure your OS and applications to
use the second raid set to host the swap/cache files. and the first raidset to host the OS + appliction binaries.

for data you can a third card with 4 disks set to raid5

now you have a next to real multimedia rendering PC ;) the real thing would use SAN or scsi disks and lots of them ;)

yep, the raptors cost, you did not make it clear whether money was a question ;)
anyhow, raptor will always beat the sata due to two factors;
- the raptor capacirty set at 150gb tells you that it has less physical movement in comparison to 500gb or 1gb disks. what this means is that the needle head ont he disk disk platter has less movement hence is faster when performing I/O changes on the disk
- the 10k rpm speeds up the seek

in single large files, you might experience the sata to perform just as well or better but with average small files, the raptors will definetly beat the sata 7k rpm disks.

since you have not elaborated on what your aim is its hard to tell you what the possible best configuration is.

one thing is for sure, no matter what, DO NOT USE SOFTWARE/OS RAID NOR MOTHERBOARD INTEGRATED RAID STUFF!!!!!!!!! the best sata raid controllers that i have come are 3ware and some have been talking about promise, the lator i can not comment as its product line has totally changed since 10years ago the last time i used promise products.

but in short if you are working with linux, just get smaller disks for the os, lets say 80gb 7k/rpm sata2 disks
add another pair of disks of same specs for swap/cache. have both configured with software raid mdadm (comes with linux). lets presume you have a MB with 4-6 sata controllers. connect the disks 1-4 to the mb
and create the raid with mdadm raid in such a manner that disks 1 and 3 (each on a different controller plugs) and respectively 2-4.

when you look at the motherboard you often see that you have two parallel sata plugins and several of those depending onthe version of your motherboard. each pair often works thru its own bus and in more rare cases thru a separate asic. so when you greate a a raid from two disks with each disk from a different path on the motherboard, you are ensuring that there wont be a congestion and have more bus space for data transfer. if both of the raid1 disks were to be on the same bus behind the same controller, then you would have the I/O traffic for both of the disks travelling down the same path and consuming bandwidth transfer capacity.

now when you create two raidsets of raid1, you still might need a separate data storage device, for that you can use raid5.

my previous personal linux server was setup so that i had 2x 80gb pata disks as raid1 for os+swap (swap enabled without raid!!! where swap partition on each disk of the raidset was its own separate swap partition that was not mirrored!!! if you mirror swap you are congesting your performance!!!). in addition, i had 4x sata 160gb disks setup as raid5.so with this setup i did not face performance issues.