My Monitor was working fine yesterday then the screen went black and I assumed it just went to sleep because I wasn't using it and now it isn't working. It will turn on but the screen display will say no VGA or HDMI detected I've tried switching the VGA cable and it still has the same problem so I know it's not that. I looked online and I could only find answers relating to graphics cards and secondary monitors but it's nothing to do with that because it's just a bog standard PC no fancy graphics card and I only have the one monitor, any suggestions please I'm desperate?!