No signal after restart or shut down.

When I try to shut down my PC, all fans e.t.c. turn off, and display cuts, but if I turn power back on, my monitor displays no input. The problem is the same if I restart, only my computer does not turn of at all. If I hold down the power button, I can make the PC boot into safe mode and into Windows through UEFI, but I cannot install updates for Windows, or turn off my PC normally. When I turn the power back on, my monitor still has no signal, but occasionally, my PC fans e.t.c. will stop, and start again, but still no signal. I have tried reinstalling all drivers and installing MSI monitor drivers, but nothing has changed. I am running a 6750xt GPU and the MSI AG321CQR monitor.

Any suggestions would be very valuable, thanks in advance.