Recently, both my monitors would randomly lose signal. Sometimes right away after booting, sometimes after a few hours. They don't turn back on until I restart the computer, sometimes. One monitor is plugged into my graphics card (gtx780) using mini display port, and the other is plugged into my motherboard using vga. It's always worked before for a year, but something is making them both lose signal simultaneously. Computer still runs in the background, I was able to turn a YouTube video on and off by guessing where to click.