New PC randomly freezing, going black screen and then back to normal

I finished assembling my new PC a few days ago and from the first time I booted windows up it does this weird routine randomly when doing simple tasks like opening windows start and opening programs:

First it freezes the programs for a few seconds (Mouse hover effects stop showing) but I still can move my cursor normally, waiting around or clicking something will make it go to the next stage:

The cursor also freezes and nothing responds for 5-10 seconds.

After this the screen goes black for 1-2 seconds and then everything comes back up like nothing happened, no error messages show up, the command that triggered the freeze happens normally and I can keep using it (rarely it freezes up for good and I have to do a hard reset).

This doesn't seem to have a consistent cause because the same tasks sometimes cause it to freeze and sometimes don't, sometimes I'll get one freeze after the other and sometimes it'll take a few minutes. The problem also persists through windows reinstalls and CMOS resets.

I didn't notice any strange behavior while watching MSI afterburner and windows resource manager graphs but I'll admit I don't know exactly what I'm lookin for.

Specs:

MOBO: Asus TUF GAMING X570-PLUS/BR

CPU: Ryzen 7 3800xt

RAM: Corsair VENGEANCE RGB PRO 16 GB @ 3600mhz

Video Card: Zotac GTX 660Ti amp! edition

PSU: Seventeam ST-550PWL

My monitor is brand new but my GPU and PSU are leftovers from the old rig, both have been acting up a little on the hardware side (noisy fans mostly), but I cleaned inside the PSU, cleaned the video card and reapplied thermal paste to it and they were working fine on the old rig. I believe I've updated/installed every driver I could.

Now I've run out of ideas as what could be causing this, maybe not enough power being supplied or GPU starting to die? Kinda weird how it works fine until it doesn't though