Like most on the people here with issues like lockups,freezing and bootout of the PC, I found out the NVDIA Beta Drivers was making my Skyrim Experience a living hell,I uninstallled Beta drivers from Nvidia,Then revert to the previous
and youre set, Hopefully this will help

I thought you ment Nvidia BET drivers are causing the issue
I have the latest non-beta drivers installed, and its still a mess (with the shadows)