After several hundred hours with several characters & on my 3rd play through, GOTY edition with all the DLC's & NO Mods, the mouse cursor has decided to spasmodicly bounce from corner to corner of the screen & when I pull up the Pip-boy or any treasure green screen the cursor won't point where I want it too within the Green Box. It does settle down & behave for 5 minutes but then throws a spasm again.
As for the stutter, whether I run or walk the screen freezes for a fraction of a second then continues. It does this every 3 to 5 steps.
I've scanned the whole PC for mal/spy or virus problems but it's all clean.
The mouse is Microsoft Basic Optical 1.0A, USB compatible & short of a hardware breakdown I'm at a loss
My other games are unaffected & the cursor behaves normally when using the desktop.
I did find the graphics set to 1280 x 780 {letterbox} & not by me, I put it back to 1368 x768 where it used to be. I've had no crashes or power outages for ages. Please throw some ideas at me.