When you installed Omega's drivers, what version did you get? Also did you get eh small update for RadLinker? It cleared up several issues with that handy little program.
Also, did you set up the drivers to have FastWrites on or off (Some 9600/9700 cards have issues if they are turned off).
In addition, have you tried using DriverCleaner to completely remove all ATI Drivers (both Omega and OEM) before installing Omega's latest? This is very important else you can get really hairy conflicts. My recomendations are as follows:
Get the latest release of Omega's ATI drivers.
Get Driver Cleaner 3 (free)
To use driver Cleaner effectively and safely:
SET A SYSTEM RESTORE POINT!!
1. Unplug your NIC (net connection). Use the Add/Remove CP to remove everything ATI including the drivers and CP
along with anything Omega. The computer will want to restart. Do it but be sure that it restarts in safe mode! (press F8 directly after POST)
2. Windows will try to do it's auto detect and install of a VGA Compatible Display Controller. Cancel this operation.
3. Open Driver Cleaner
4. Under the Tools pull down select Cab Cleaner and clean drivers.cab (takes a few minutes)
5. Return to Driver Cleaner main screen. Have it clean ATI (do all ati related cleanings to get everything)
6. When it completes, empty the recycle bin and restart
7. Again cancel windows auto install.
8. Run Omega's installer (if you're running XP be sure to say continue anyway when its does the not signed alert)
9. When asked to restart, click no and immediatly install the radlinker update.
10. Restart, and give it a shot!
If the above still has issues, use RadLinker (accessible via right-click) to turn FastWrites on and try again. If you are still having issues, consider trying a different rendering protocol in CS. I'm not sure what is supported by CS but would assume it has OpenGL compatibility. If THAT doesn't work........well dang man I'm fresh out of ideas! Good Luck, shoot any questions you have!