PC monitor keeps going black but the tower still runs
hello there, my desktop PC keeps randomly having the monitor go black with a message coming up saying no signal however this is not all. if i am watching a video it will loop the sound also, so its just turns into an elongated humming noise. does anyone know what to do? i have taken it to a technician he said he took it apart and rebuilt it and left it on for around 2-3 days and this didn't happen. over the course of 10 days he tested what he could and still did'nt know. i got the pc back around 3-4 days ago and it's only just started happening again. i have 7 fans and a big cpu heatsink so im not sure its temperature.
the computer remains on and humming normally throughout all of this. i have tried different hdmi cables also and no difference.
what info would you guys need?