I'm not very good with computers but I have a custom built gaming PC that has worked very well for me for quite some time now but recently has stopped turning on. I press the power button and it lights up but nothing inside "whirrs to life" so to speak. No fans nothing. I replaced a fan in it about a month ago and it didn't happen for about a month But now it's happening again and I don't know what to do. Any help is appreciated.