New
#11
If his problem is simply driver-related, I agree however if he has a hardware problem (remember that's a 9800 series video card, it's quite old), no amount of driver tuning will resolve a card that's failing at the hardware level, the most logical step is to make certain that the hardware is not faulty. Driver tuning on a pre-existing operating installation will NOT identify a faulty card.
A compromised Operating System installation can cause problems even when the drivers are installed properly. This is why it's best to test the video card on a separate hard drive with a fresh installation of Windows (32bit to match his real system), load the correct software and drivers and test it out that way. If the video card performs properly then it's very likely that the hardware is in good shape. If it doesn't work properly despite a new OS install, new drivers amongst other things, then it's likely the card is bad.
All in all I hope it's just a matter of him clearing out outdated addons for his WoW game and simply updating to the latest Radeon driver set from AMD/ATI. If that doesn't work however...