In the past, I have seen issues with the 9800 card, so trying another one might help.
Are you being asked to load any special drivers, like RAID? I will assume you have the bios set up to use RAID. I have never run RAID, but I beleive the largest partition useable is 2 TB. Is your RAID partition larger than that, if it even works that way?
Using a non-RAID install might be helpful for testing.