Also with the whole no input detected thing, I had a monitor that did that, and it was the cord going from the monitor to the PC that was dying out. After I replaced the cord, it started working fine again, but then the problem started again. It'd work for a bit, but then go blank randomly. So I decided to bring the monitor in to my friends shop, and when he checked it out, all the little bulb thingies in the monitor were fried. So it could be 1 of 4 things so far. A - The gfx card is giving out, B - the cords are starting to give out, C - stuff is overheating, or D - Your monitors bulbs are slowly getting fried. I'd say try to narrow it down by trying a different monitor to see if the problem still persists, and replacing cords, then go from there.