Re: Startup issues...black screen
Computers come with either an o/s disk, or there fake stuff that they save money on. All store bought computers come with sometime of reformatting disk. If he can't find it, he's screawed. Just kidding, he can buy a new o/s they cost about 100$ on ebay usually.
Now that I think about it, sometimes a cmos reset fixes the problem.
Tell him to check his manual and look up cmos. It tells you how to reset them, that might save you some time, and if that doesn't work then he needs to reformat.