HD Upgrade Path??

[GSXRAbuser]

I currently have a 74 GB WD Raptor and an old 80 GB WD IDE drive that I used as storage. I have 4 drive slot bays in my machine and I am pondering if it’s worth adding another 74gb raptor to RAID - 0 it and make that my OS/Games drive and purchase another 2 drives for data in RAID 1 or buy 4 sata drives in RAID 10 and bust that up with different drive letters for my OS and Data. I don’t plan on purchasing a RAID card unless it’s absolutely necessary; I was hoping to do this off of the ICH9R chipset on my motherboard. Any suggestions would be extremely helpful.

Thanks