I am also getting micro stutters yesterday after I had a Windows update which install some security stuff on Friday. Overwatch turning was stuttering randomly and badly. Turned out, I went from 165Hz to 85Hz. I tried to increase my refresh rate but both Nvidia control panel and Windows 10 Display Settings shows the highest to be 85 Hz. Minitor's Overclock still shows 165 Hz.
After a restart, I managed to pick the 165 Hz on Nvidia Control Panel but Overwatch was still showing my highest refresh rate along with the different types of resolution as 85 Hz. Keep on closing and reopening and using Nvidia Control Panel -> Manage 3D Settings and Program settings but it was already set to Use 3D application for Set Vertical Sync.
So I opened the game and pulled the DP cable and reconnected. Black screen with the mouse. So I Windows out of the game and re-enter the game and voila. 165Hz can be picked with all the resolutions.
But right now, just a moment ago when I turned on my PC, my screen went blank on the lock screen prior to logging in.
I turned on my TV but nothing was displaying on the TV. Then I turned it off and my monitor refreshes and shows the lock screen.
Upon logging in, I was getting the error, "Application LockApp.exe has been blocked from accessing Graphics hardware" repeatedly more than 3 times like about 7 but only 3 shows up on the notification column.
Looks like I might have to reinstall the graphics drivers or it could be Windows "Security Update for Microsoft Windows (KB4038782). Gonna bet it's the latter that broke the Nvidia drivers.