I have an HP a6537c desktop computer, I never really had any problems with it but now I am not sure what could be wrong with it.. It powers on, and all the fans run, but none of the USB ports will work, and the cd drive when pushed opens, then closes quickly. I have a graphics card that I put into it, and when I plug the HDMI cable in it just says monitor going to sleep, I know the HDMI cable is good, and the graphics card is working. If anyone can help me find a fix for the computer it would be greatly appreciated.. It was running fine until today.