upgrading failed raid drives
My fathers' computer has recently had a hard drive fail. He has a raid set up that I originally thought was raid 0, but must be raid 1 because it is working as a redundant drive in case one of them fails. Unfortunately the other one failed before I got around to replacing the bad drive. My dad recovered the drive and it booted up, and now he is backing up his stuff.
He wants me to upgrade, if possible, his hard drives. I would like to get him some 500, maybe 640 gig hdd's that are faster. Maybe caviar black series? He currently has two samsung HD320KJ. Is this even possible? Since it is in raid, can I upgrade? If so, please tell me how and if you have a suggestion on faster drives that are not raptor-priced, I would be much appreciated!