I'm posting this because I've run into this problem several times now. And on multiple machines. Windows update has been making a bad habit of downloading drivers that the user had not authorized. In my case, AMD graphics drivers are being downloaded and installed silently by windows update manager. This then causes the Adrenalin software package to bug out and crash when it tries to automatically update itself. The effect, random and aggressive hitching and / or sudden black screens while the drivers try to recover from a crash. You may even see a warning message popup stating that your hardware has changed and your system requires a restart. So, if anyone else notices their system showing those symptoms after a windows update had recently installed, try manually updating your graphics software and drivers from your graphics card vender's web site.
