Since you spoke of reinstalling, did you fabricate the installer for your OS using Windows Media Creation Tools? You will also need to mention the make and model of both PSU's and their age. To note, might want to see if your motherboard is pending any BIOS updates. Speaking of which, what is the make and model of your motherboard(s)?
Latest drivers sourced from Nvidia's support site and installed in an elevated command? i.e, Right click installer>Run as Administrator? Got a link to the GPU you're using?