Generally what happens with my GPU is that after a power loss or restarting, the GPU Core Clock will be stuck at 300MHz. Memory clock is fine. But this leads to poor performance in games (less than 20fps, if not 10). If I reinstall a driver (7790 specific, 13.4, or beta) after using the AMD driver uninistall utility it will clock properly for one more session. Reflashing the bios will fix it for one more session as well. But all it takes is restarting to mess everything up again. I don't think it has to do with overheating either; I can restart after playing a game or just doing light desktop stuff -- same result.
I have been doing a lot of investigating and it seems like a lot of other people are having problems with this card based on what I've read on at least two other message boards. Apparently it has to do with the power states? Not sure but I think that's a safe bet. Either way I think this needs to be addressed. Seems to be too widespread of a problem with the 7790 GPU. Any ideas on how to resolve this?
Mobo: MSI 970A-G46
CPU: AMD FX 6300 @ stock
RAM: Crucial 8GB DDR3 @ 1600MHz
GPU: Diamond Radeon HD 7790 (7790PE51G)
Power Supply: Seasonic M12 SS-500HM 500W
OS: MS Windows 7 x64