OK, this worked for me, but first i'll explain in detail. I had white screen of death always on, my flex 10 would not turn off, with the light beside power button on RH side continually flashing in standby mode. I thought I tried every combination on keyboard to start flex 10, but nothing worked. However, this worked for me. Holding down the Fn and F1 keys together, started the Lenovo boot logo and booted into the Microsoft login screen, all solved.