-1 to all of that.
It's merely a matter of a driver issue. Especially if you just changed graphic cards!
I had the same problem (different card tho), and so do others:
http://www.lfsforum.net/showthread.php?p=537768#post537768
Eventually for me the solution was:
1. Download ATI catalyst drivers 8.1 (hotfix)
2. Add/remove software - remove all ati drivers
3. Reboot
4. Go to save mode (press in boot screen)
5. Run driver cleaner (however this doesn't clean everything either so do 5.1 as well)
5.1. No driver cleaner? Remove:
- C:\ATI
- C:\Windows\ - search for ati*.*. Remove all these items
6. Run the reg cleaner part of ccleaner, remove all obsolete keys
7. Reboot to normal windows
8. Install 8.1 hotfix, wdm drivers (and if you want, ATI Tray Tools)
These steps did the job for me.