Hi, sorry to bother you all.

Recently I have encountered a problem with my custom built computer. After seemingly random intervals of time (10 minutes to 7 hours), my computer displays and sound shuts off without warning. It says "no signal" on my monitor and the PC fans and lights are still running. It doesn't seem to matter what I'm doing on my computer before it happens (it has happened while browsing Reddit, and has occurred whilst playing games).

I have tried cleaning out my PC for dust, updating drivers, reseating ram and graphics card, and reflashing the bios. I am not very experienced with troubleshooting PCs and would greatly appreciate your help.

Thanks.