It does not tell us if it's cable, connections or the video card. The cheapest part would be the cable. Try a shiny new AmazonBasics cable.
Also, if this connection is unplugged/plugged hundreds of times a month, you could wear out the HDMI ports. That's costly to fix. Try the cable first.
I recently bought my PC 5 months ago. By the 3rd month, my PC makes electrical noises followed by the monitor being disconnected. The disconnection takes about less of a second. I noticed that as time went on, it just gets worst. It occurs whether I am gaming or just browsing the internet. Someone please help me.

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