http://www.ultimatebootcd.com/ has an assload of hardware diags on it and it runs after booting from cd. if there's any way he can get it himself, cool. if not, you could mail it to him cheaply with usps media mail. memtest86+ would be where i'd start. you can run the hard drive diagnostics to test failure on that, prime95 for overheating/motherboard stability, etc.