I have tested 3 different machines with 3 different displays and they all have this graphic issue showing up in multiple games.
Lenovo Home Desktop (onboard intel graphics)
Windows 7 32-bit
Asrock P67 Extreme4
Intel G860 CPU
GSkill 4GB RAM
Windows 7 64-bit
Asrock Z77 Extreme4 / Biostar TZ77XE3
AMD 7950 (also tested onboard)
Intel 3570k CPU
WD 500 GB / OCZ Vertex4 SSD
8GB Corsair RAM
Windows 8 64-bit
The issue is mostly showing up in the bottom left hand corner, it isn't as noticeable on some of the computers, because they have different brightness / contrast, but I does show up on all of them. Also, in the foggy areas, there are color banding circles covering the screen.
I also see terrible color banding / texturing on loading screens for games such as: Bioshock Infinite, Assasins Creed 3, Battlefield 3, and I see similar issues that are shown in the Diablo 3 screen shot in: Torchlight 2 (dungeons / outside), Bioshock Infinite (light areas / sky), Minecraft, BRINK.
Anyone know a fix for this or am I just going to have to deal with it? I never noticed it before until I got my new AMD 7850, then I got a 7950, and tried a GTX 650, and onboard Intel HD 4000 graphics, and it shows up on all of them. I wonder if all the new graphic drivers have something in common.
I tried contacting AMD support and Blizzard support, and they all told me to go through the basic trouble shooting steps, that I already thought of, and nothing has fixed it. They both are stumped on this issue, and can't find a solution.
DVI, VGA, and HDMI cables
Tried changing settings in AMD control panel
Tried various changes in Diablo 3 and other games
Tried multiple driver versions (13.1, 13.3, 12.4, 12.8 / Microsoft driver)
Does anyone notice the banding issue much in the screen shot? I know some people who have seen it say they can't really see it and others can. I am guessing it is a common driver or software issue now, since it is happening on all of the computers I have tested, unless somehow all my monitors are defective.