Stuttering after system upgrade

Hey guys.

I recently updated my system to
AMD FX 6300
AMD R7 370 4gb
8 gb ddr3 ram
Win10

Now I have a strange stuttering, even in the menu. It's like every sevond there is a little drop in frames and in between everything is okay. So it isn't normal low cpu/gpu Power. Tried without Controllers plugged in, same Problem. Rf2 and gsce work fine.

Thanks for your help ;-)