I have windows 10pro and no matter how many times I reinstall the system whether on uefi or legacy I have the same problem:

When I start windows from zero(power button) I have low fps and stuttering on games. But when I restart(not shut down) the pc frames are perfect again.

This happened to me with 2 graphics cards r9390x and gtx 1080. Of course everything updated.

This is what I tried:
-Fresh install both uefi and legacy and with and without microsoft account login
-Java and flashplayer install
-different resolutions
-and several other things I canīt remember.

If anyone has a solution for this It would be highly appreciated.

Thanks in advance!