Try installing the *NEW* Catalyst 4.4 drivers
If that doesnt work, get the omega drivers, here: http://www.omegacorner.com/index_ati.html
If that doesnt work, uninstall the game, reinstall the game, and see if it will work.
And last but not least, if you havent already, check DXDIAG by clicking Start, then Run, then typing DXDIAG, then click OK, then click the Display tab. This should show the main display adaptor that is being used. Make sure AGP Texture Acceleration has "ENABLED" shown, and also make sure it says the name of your Sapphire ATI Radeon 9600 XT.
If none of these work, either I will give you some more suggestions, or some other people on here will, because some of them know alot more than me! :P
Anyways, good luck, and I hope these suggestions get ya working again!!!