I usually locking my PC using Win+L and after minute display switches to power saving mode (turns off) or it turns off after 15 minutes of inactivity. Once from 5—7 times display shows black image after resuming from power saving mode. To "fix" this I have to turn off my monitor using on/off power button. This bug is very annoying.
Windows 8 Pro 64-bit
Intel DZ68DB Desktop Board
Intel Core i7-2600K CPU
Intel HD Graphics 3000 and DisplayPort connection to NEC MultiSync PA231W monitor.
All drivers for Windows 8 had this issue, including the latest version 126.96.36.19932.