New Build Suddenly Died

I just built my first computer, it's been working for about a day but then I was playing a game and it suddenly powered down. Now when I try to start it, everything inside the case seems to work like it should, except the fans are spinning pretty fast. All of the motherboard lights are fine, and so is the beep code. There's no signal to the monitor, and sometimes I have to press the power button a couple times to get it to shut off. What's going on, this is driving me crazy.