I am having a lot of problems that seem to stem from my AMD GPU.

I am running the retail version of Doom 3 with the 1.3.1 patch. The screen resolution won't save.

I also can't run any mods.

After reading complaints of the same problem they all seem to point to having an AMD GPU and CatalystAI.

My System:

CM Storm Scout, AMD Phenom II X4 965 Deneb Black Edition @ 3.4Ghz w/Cooler Master Hyper212, MSI 870-G45, Corsair XMS3 4gb (2x2gb) 240-Pin DDR3 SDRAM DDR3 1600 @ 1600 Mhz, Sapphire Radeon 6870, WD Caviar 500gb, Sony Combo CD/DVD, Corsair Modular HX620

Most DOOM3 mods are made for nVidia cards, so you must disable Catalyst AI to play them. If you want to play a fun one without disabling Catalyst AI, try Denton's Enhanced DOOM3. If you experience an upside-down camera view press '~' and type 'r_bloom 0' and press 'Enter' That should correct the camera. Yes, you will play without bloom, but the mod is great anyway.

Windows 7 Professional 64-bit
AMD Phenom II X4 970BE Deneb 3.5GHz CPU
ASUS M5A88-V EVO Mother Board
2 X 2GB CORSAIR XMS3 DDR3 1600 RAM
XFX AMD RADEON HD 6770 1GB GDDR5 GPU
Dell D1626HT Trinitron 21" CRT Monitor
Seagate Barracuda 160GB 7200rpm SATA3 HDD
Seagate Barracuda 250GB 7200rpm SATA3 HDD
Seagate Barracuda 2TB 7200rpm SATA3 HDD
ASUS DRW-24B1ST SATA DVD-R/RW
Corsair GS500 Gaming Series 500w PSU
CoolerMaster HAF 912 Case