FIRST LET ME SAY THIS IS NOT A FIX!!! IF YOU MESS UP YOUR PC BURN DOWN YOUR HOUSE OR BREAK YOUR ARMS AND LEGS ITS YOUR PROBLEM.
Okay i have had same issues as some are posting here, i was ready to "fix" my PC using something heavy.
But then i remembered something MS is infamous for make your permissions F.U.B.A.R so i checked my permission to my own user folder
and guess what they had changed to READ and EXECUTE nothing else.
That means no saving settings no changing anything so i wen't back up the folder tree to C:\Users and my checked the security tab, well i also happen to click the sharing tab and i almost chocked om my coffee,
The C:\Users folder was shared and how that came to pass i have no idea but what that means is, i had 2 entries in the security tab 1 said full control to my own folder as it should , BUT because top folder was shared i also had permission that would only allow me to "read and execute" and it does not matter if your God himself or what ever those permissions will over-rule anything else even FC.
I checked further and looked at C:\Users\kimkl\AppData and i was speechless my username was not listed at all and SYSTEM was the owner of the folder that should have been me listed as the owner.
I checked this just to be sure on my "twin pc"
Okay the "FIX" for ME!!!! was simply to enable the Administrator AC and use that i tried fixing the permission for kimkl so i do not have to use the Administrator ac but no matter what i do my PC will not let me do anything like right click or enter start menu and my HD's play hide and seek on every reboot, but after i enabled the Administrator ac and use that my PC runs smooth no troubles no screen/monitor going black changing res or fps on me.
The only downside every program i own has to be activated again, this was the solution for me.
If you follow my way and "mess up" well 1 word TOUGH!!!!
Thank you