|Just out of interest, exactly what question did you pose to Microsoft when you say they had 'no solution'? From a tech point of view it's a hardware fault not a software one.|
Anyway, is the XP disk a genuine one? You state there's nothing wrong with the disk, but as you have tried it on three different machines I would really suspect that your faith in the disk is misplaced.
Final point, the first thing to do before replacing a recent machine with XP is to check & make sure that the drivers you'll need are all available - so before you wipe off Win 7, make a note of the exact hardware that you have to make the job easier.
"I've always been mad, I know I've been mad, like the most of us..." Pink Floyd