r4pture^ sounds to me like you have an AMD video card. Unfortunately, AMDs Linux driver support has been sub par for some time, however with the new 3.12 kernel that seems to be largely fixed....well, not fixed, but greatly improved.
http://www.phoronix.com/scan.php?page=article&item=amd_linux312_major&num=1
I do. I have a 4670. Those benchmarks look interesting. I might have to try again when 3.12 hits the Arch repositories. Hopefully there's more support for AMD cards in the next couple months with the steam box coming.