Monitor goes black and says no signal input

Yeah I mean it doesn't happen as much but sometimes maybe like once an hour, the game will just freeze for a couple seconds, then the screen goes black. But the computer is still running fine and the game is running fine I can hear the sounds and whats going on but I can't see anything and the monitor says no signal input. I turn it off and back on and it still doesn't work I have to restart the computer. I was wondering if maybe it had something to do with my graphics card, or if anyone has experienced this before. Maybe something I could downoad to fix it? Thanks for reading and any help givin is much appreciated thanks.