Just downloaded/installed 4080 drivers Jan 15 build. NUC i5 running Win 8.1. No games. DP connection to a Dell U2414h. Coming out of sleep, heavy artifacts/flickering displayed on sign-in screen, desktop screen, and "metro" screen using latest driver 4156 and 4206 beta drivers. Also one instance where screen was just black. Re-start Dell monitor brings it back to 'normal'.
So far, 4080 drivers are much better at not leaving artifacts and flickering when coming out of sleep. Will keep testing for a couple of days more.
I'm convinced after 2 days of testing sleep mode in Windows 8.1, I haven't had any occurrence of the screen artifacts using the old 4080 drivers. Tested going into sleep mode for 30 minutes, no issues upon tapping the keyboard to return to log-in screen. 8+ hrs of sleep mode comes out perfect using return to desktop screen.