Laptop or desktop?
The only relevance being that a laptop is lighter to throw through the window
Not so, young hound. If it's a laptop, SOMETIMES, taking the battery out, putting it in a plastic bag and lobbing it in the freezer for an hour, then re-installing it can somehow revive it. If a desktop, remove the power lead and hold the on/off button for at least 30 seconds. Then put the lead back in and try also SOMETIMES works.
So there.