I am having serious issues with my PC and I am looking for advice about what to do now. I think it could be PSU, motherboard or virus, I am just not sure. For quite a while my computer monitor would go black but all PC lights would stay on and if I turned it off and came back later it would all work again. This happened for a while but now when you turn the computer on windows is virtually unresponsive: The internet does not work despite full signal, you cannot get into the "check for update" section (continuous whirling ring) although strangely I can still play hearthstone. The battle net live ads on the log in screen fail but I can still get into the game and play on the servers. It is literally the only thing on my PC which works. Avast will not open if clicked, I can open CCleaner but if I try and clean the PC the bar doesn't move. Trying to use the majority programs will fail. I managed to get the internet temporarily 2 days ago, I ran an update hoping it would fix it. However when I restarted I got a random "windows is not genuine error" which has since disappeared but things are the same. In terms of possible issues a fan at the front of the case is rattling and a major rattling sound (on and off) is coming from what I think is the PSU. This rattling is new, it did not happen when the random black outs started. Could this be the PSU? Would it cause windows to seize up despite cpu/ram usage and temperature settings showing not much is happening? or could this be a virus? I am hoping to do an avast boot scan but I cannot open the program.