My monitors or my PC keep turning off without warning

Hey guys, i'm having an annoying issue with my PC. My PC will randomly turn off in the middle of a game i am playing, or my monitors will jjust go black without warning with my PC staying but all sounds is gone. If i hard turn off my PC with the power button and try to turn it back on, the PC sometimes will not turn on. Other times, the PC will turn on, the monitors will turn on but still show just a black screen. I am then only able to access my monitor when I unplug one of my monitors from the graphics card, and it's usually one specific monitor. Once i unplug that monitor I am able to see the other screen, but then my mouse is unresponsive!! I have no idea what is going on.