Here lately I've been having a problem with my monitor going black. So far it hasn't happened while I was using my pc, only if I leave for a while and the screen goes into power save mode. Then, when I move the mouse I get the "no video connection detected" message. Shutting down the pc and waiting awhile before restarting seems to fix it, which makes me think it's an overheating problem. If so how can I tell if it's the graphics card (Radeon HD 7770) or something else? I've already done all the obvious things, such as replacing the HDMI cable, making sure the pc was free of dust, reseating the graphics card, etc. Any other ideas?
Instead of restarting the computer, try turning the monitor off and then on again. I have a 26" monitor that occasionally has this issue, and has had it for the last 4 or 5 years. In my case, I'm not sure of the cause, and really don't much care. It takes just a few seconds to cycle the monitor.
