External monitor intermittantly dark

My friend's new Sony laptop has an external monitor connected via HDMI. When he restarts the computer, about half the time the external monitor is not getting a signal, it is blank. He then restarts it until it works. I've only connected remotely to it, and I've been able to get it to go on by playing with the settings in Display properties. Possibly if I was in front of the computer I could try Fn + F5 to see if that works, but he is the kind of guy who does not want to press keys to make it work, he wants it to just work. Any ideas what might be done to make the second monitor get a signal on a more consistent basis?

Thanks

Replace the internal pcb inverter board, or it might just be the caps that need replacing. A third possibility is a weak connection (cold solder) at one of the backlights.

Only way to keep it on until it breaks completely is to lower brightness and contrast to 0 or near 0, and don't let Windows turn it off ever.

...or chuck it in the trash.

I was able to get the external monitor to work by changing some settings in Display properties - not sure which ones it was, but they were setting related to choosing which monitor is on the left and right, which is primary monitor, etc. I don't expect it is a monitor hardware issue, more likely a Windows problem, with Windows not retaining these settings.

Nah. If you start the computer and the monitor is blank, the monitor is defective as per above. They don't care if they're left or right or anything like that (primary or not.)

Now if you start Windows and the monitor is literally disabled in the res. settings screen, then that's another story, but I don't think we're talking about that.

Intermittently = likely one of the 3 possible problems above.