I'm at my library right now. My desktop broke down and I've been using my laptop as backup. But now I remember why I only use it when I have to:
At any random time, the screen will become heavily pixelated. Even if I have a desktop monitor connected to it as an external display (like what I have now), even the desktop monitor will still dispaly heavily pixelated garbage.
Sometimes, I can reboot the system (which, since I can't see what I'm doing, will usually involve taking out the batter and unplugging the AC adapter), that can solve the problem, temporarily. However, it's getting to the point where it's pixelated as I turn it on!
Here's an image that vaguely (though not completely) resembles my problem:
Now here's the thing: I remember, in summer of 2016, taking the laptop to a local computer shop. This shop shut down in December 2016, so I can't ask this guy what he did. But I remember him pressing some keys on start-up and it rebooted with a legible display. Basically, what he must have done is go into the BIOS and rooted around there on pure memory to get it to switch video processors or something like that.
What's more? He seemed to know exactly what to do! I turned on the laptop and showed him the pixelated start-up screen, and he was just like "Aw, okay," and he started pressing buttons, and in approximately 30 seconds, the screen was back to normal!
So, there's definitely a quick fix, even if it's only a temporary one. I don't have to keep turning the laptop on and off constantly for an hour until I get lucky and get it to appear legible.
The question is ... how do I do it? What buttons do I press, in the right order, to get the laptop to switch displays?