I have had the same problem with Dell. I have a 9100 with the ATI 9700 128mb card. For some strang reason Dell is refusing to update the drivers for this card on these 2 systems. I hae fought back and forth with Dell on this issue and they still think that it is not a driver isssue. My only sugestion to you is if you can return the system and have Dell upgrade your machine to the ATI 9800 256mb card for free, then do it. If they will not try these drivers. They worked perfect for my system.

 

www.omegadrivers.net

It is not the game or system. Could be related to the current Dell ATI drivers. I'm having the same issue and from what I've heard others are to using different system. They fix the issue by updating their video driver but Dell has not release any new drivers for their Raedon so we would have to wait for Dell or ID to patch the game.

I downloaded the latest drivers from Dell and it still didn't work. I tried the games with hyperthreading turned off. It' seemed to work. If you don't know how to do this don't woory it's easy. At start up hit F2 and go into page 6 or 7 and disable Hyperthreading. I only played Doom 3 for like 10 minutes but like I say'd it seemed to work. Please repond to this if you also have success with hyperthreading turned off.

It's related to the video drivers. The one posted on Dell website isn't the leastest ATI has to offer, we might have to wait 6 months before the current supported drivers that ATI has be repackaged for our Dell system.