Question Monitor suddenly goes to D-SUB No Signal

[argitis]

Hello. So for about a week, my monitor at random times during the day (no more than three times) will lose signal and will display the "D-SUB No Signal" error. At the same time, there is sound from whatever I'm watching on the monitor, but after 2-3 seconds it will lag and the only way to fix this, is to restart the pc. I've noticed that most of the times, this will happen after I stopped playing any demanding game (i.e. pubg with settings set to ultra, ets 2 with settings set to high).

The specs are:

Motherboard: B550 AORUS ELITE V2
CPU: Ryzen 7 5700X
RAM: 2x16GB Corsair Vengeance LPX DDR4
STORAGE: Western Digital Blue SN570 SSD 500GB M.2 NVMe
STORAGE: Western Digital SN770 SSD 1TB M.2 NVMe
PSU: Corsair 850W
GPU: MSI GeForce RTX 3060 Ti 8GB
SYSTEM: Windows 10 Pro

What I've tried so far:
1) sfc /scannow
It found some corrupt files, it fixed them, the issue still persisted.
2) Reinstalled the gpu drivers through Geforce Experience. Issue still here.
3) Changed the VGA cable that goes from the gpu to my monitor. Because it's an old monitor it doesn't support hdmi cables, so I have an adapter that goes from hdmi to VGA. That is the only cable that I haven't changed, because I'm still waiting for the adapter to be delivered.
4) Cleaned the entire PC. Cleaned the gpu, the ram and the cpu fans. It still happens.

Besides the hdmi adapter being the issue, any thoughts on what might be causing this?

 

[Lutfij]

PSU: Corsair 850W
Corsair is the brand of the unit, while 850W is the advertised wattage of the unit. What is the model of the unit and it's age? Have you tried sourcing(borrow, not buy) a reliably built PSU and tried powering the system with it to rule out your PSU to be the root cause of the issue?

BIOS version for your motherboard?

Reinstalled the gpu drivers through Geforce Experience. Issue still here.
Use DDU to remove all GPU drivers(Intel, AMD and Nvidia) from your platform in Safe Mode and reinstall the latest driver sourced from Nvidia's support site in an elevated command, i.e, Right click installer>Run as Administrator.

sfc /scannow
It found some corrupt files, it fixed them, the issue still persisted.
I would also try and reinstall the OS in offline mode, after recreating your bootable installer, then manually install all drivers in an elevated command, to root out the OS being the issue.