My friend's laptop had no display and fractured display on external monitor. I replaced mobo and copper shimmed the graphic chip. That fixed that problem but now a different display problem.
Now on cold start, internal display is black. I found by 3-finger salute (Ctrl-Alt-Del) immediately following on-switch the display lights up but usually only after numerous trys.
Hours of experimenting revealed that by closing the lid immediately after pressing the on switch, the display is lit when I reopen it. This seems to work every time and I can now live with that but I am not so sure my friend will.
Hope this tip helps some folks but I am still seeking a better fix.