Originally Posted by ASUSEN7900GTX
i have a 8800GTS 640mb 1280x1024 i use the AA option where i can choose 32xS and enhance AA ingame and i use the AA+HDR oblivion thiingy
32xS might be a little over the board. It requires a huge amount of memory, but there could be other reason why this mode causes problems with Oblivion.
Try to reduce the AA to 16xQ. It should fix your problem. If it does, you can try 16xS or 8xS if you prefer Supersampling AA with Oblivion.
But I think 16xQ and Transp. MSAA is the best combination for Oblivion.