But it sounds like he doesn't know exactly what it is. Though I suppose the only clean solution would be to return it all, like you said.

My dad's work machine had bizzare issues. It would load certain things, like network drives, veeeery slowly. Eventually the Dell representative replaced the memory, ghosted to a new hard drive, upgraded to Win2K (from 98SE), and finally replaced the whole mobo. When those problems still wouldn't go away, they said screw it and put it in a low traffic area. Never did solve it. I guess some machines are just duds