Try that monitor and cable to some other HDMI source.
If the cable and monitor work elsewhere, you turn your attention to the PC. Google up "The Dead PC" to learn the basics unless it's in warranty.
Hi
So I was about to game, as you do, while doing a few things on the computer, when all of the sudden while I looked away my PC restarted, and my screen showed "no input" and went to sleep mode. Tried restarting a few times and replugging the cables, dedusting the insides and what not, with no luck getting that input signal to function. I was just wondering whether I need to buy a new HDMI cable? Probably, but if you know a hack, or if the issue is something different i'd appreciate your help

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