I recently acquired an old ThinkPad T400 without a hard drive, so I put one in and installed Windows 10 on it. The first few boots were pretty painless and Just Worked, but there's some kind of problem that prevents the laptop from booting normally. This is what happens now when I try to turn it on:
- I hit the power on/off button
- The usual BIOS and whatnot screens fly by, the Windows 10 loading screen appears and disappears
- The screen turns off and stays off
- I have to hold the power on/off button for about two seconds to put the laptop to sleep, then press the button again to wake it up
When all this is done, I can login and use the laptop relatively normally. Some minor things like Fn-key combos don't work, but that's not part of this problem.
What can I do to make the laptop boot normally? Reinstalling Windows did not help.
Update: The laptop just failed to fully wake up from sleep mode. It was running, with all the important LEDs blinking, even the screen illumination was on, it's just that there's nothing on the screen but blackness.