We use Thinkpads Yoga here and I have found a cause for a strange problem we were having. One of my users complained that her computer would randomly go blank throughout the day, sometimes when she was in the middle of typing something. I checked every setting I could find, installed all the updates and it still would not go away. I gave her an older non Lenovo loaner while I was working on it and she had zero problems. I ran the computer on my desk for two days with no issues. Within a couple of hours of giving it back to her she had the same problem. I setup a new out of the box Thinkpad Yoga for her and she had the same problems, at this point I knew it was not the computer. We were talking and I found out she had just replaced the band on her watch with one that has a magnetic clasp. The Yoga's (maybe other models also) use magnets in the system to detect when the screen is closed. We found that if her watch clasp was in a certain place, the system thought the screen was closed and would go blank. Just passing this along in case anyone else runs into the same problem.