Game keeps crashing after about 20 minutes

Since the last update, my game keeps crashing every 20 minutes or so. No warning, no stuttering, no endless wait for the game to save, just shutting down. It's very frustrating.

I've removed all my mods, repaired the game, removed cache - nothing is working.

This is on PC and on a brand new save game I started yesterday. I've attached the lastCrash log to see if this helps.