fter upgrading to Win 10 Home from 8.1 and even after clean install of Win 10 Home, I get intermittent almost black screen without cursor. Programs running, like browser video continue producing sound without glitch. Ctrl-Alt Del does not work but Fn-F7 turns the LCD backlight off (darker black screen) and pressing again turns it on with video restored. The problem will recur from 2 seconds to a day later. Driver errors in Generic PNP Monitor (present in Safe Mode) and Bluetooth have been corrected by uninstalling and scanning for new hardware, but problem persists. Both sfc and dism completed without changing anything.

Win 10 Home 10.0.10586 Build 10586
AMI UEFI v. 208 (latest)
Intel Core i7-4710HQ
16 GB Dual-Channel DDR3
Intel HD Graphics 4600
SanDisk 250 GB SSD