So here is the problem, I have an AMD radeon HD 7800 series graphic card (kinda old) with an core clock off 1100 mhz normally. About a week ago when I turned on my computer it gave me an black screen because it couldn't find my graphic card, I fixed that but now my core clock and memory clock of my GPU is stuck at 150 mhz instead of 1100 mhz. I fixed it with reinstalling my drivers but when I restart my pc its stuck again and now I can't fix it anymore. Can someone help? I also just have one screen, since I saw some other people with this problem but with 2 or 3 screens.