I am al ready aware. still unknown. No idea if these is a windows issue or bios issue.
the mouse is a peak on cpu. You can test these, aside these, or not. open a youtube video. if you have 2 screen is better.
then open task manager on process. and press CPU so the top process is visiable and then open notificacion bar and see what is what.There also some ither issues like usb disconect and odd restart. etc. I am not sure why.
I roll back to 1005 and seams better. Here you will see if you add the 5ghz oc, they drop even to 46. no idea why. I am using also 3600mhz c18 memory since i did the MeUpdate i can not roll back o a older bios. is not good. so i will live with it. As far is my understanding, is windows and intel Not the board. now not sure why you have these issue. but you can check with a friend the PSU. sound odd, but try I detect my PSU is getting weird issues. like on sata, my leds (power with sata) dim. not sure how to explain, like running out of energy. anyhow. check that first.
Is just a idea.
I hate intermittents. I would much rather something just quit. It appears you have painstakenly taken the computer apart, redone all the drivers and started it with a minimum system and added each peripheral back in to see what works. Make sure you have done that exceedingly well as any step you miss is likely the one with the problem.
I had a very similar problem. Replaced memory, went to one NVME OS drive, then tried another, one stick of memory, then a different stick, then 2 sticks, then in different slots, used iGPU only and removed GPU, new larger PSU after testing PSU.. Then I got drastic and changed motherboards (went from a Hero back to a Strix) and it worked for a day. Then the same thing happened with the mouse. Decided to rma the second mobo. Got a new RMA and was ready to send it and the GPU both off for an RMA. That night I got to thinking.......the only thing I hadn't done was change the case. So rather than ship things off, I went and bought another Fractal Design R6. Reinstalled the system in the new case and Voila! everything worked. Sounds silly but true. The only thing I can think of is that somehow the fan pwm on the back of the case got a short in it and started generating the intermittent problems. So don't quit until you have tried absolutely everything, because the last thing you check will be the solution to your problem.