My graphic card is ATI Radeon HD 6850, I've been using the card for 4 years. I know it's pretty old but It worked just simply fine until this morning. This morning, my monitor just stopped working after the PC went to sleep mode, It seemed like the CPU was working as usual but there wasn't a thing on the monitor, I tried to remove the rams... nothing went up then I tried to remove my ATI Radeon HD 6850 and used on-board card instead. Surprisingly, the monitor went back and worked normally. What is going wrong with my card? Can someone help me please? Thank you.