football games just dont wanna work

[iwillrace]

OK this one has me stumped i have 2 almost identical xboxs same chip same 120 gig hd same bios same same same. One of them belongs to a friend of mine now here is where it gets weird a backed up versoin of madden 2005 or a acctual espn 2k5 will not play in his box. They both work in mine and his box plays all other backed up or origonals just fine but for some reason it wont play these two. Any ideas i tried copying it to the hard drive and same problem after the first start screen that says press start it goes black no response. But just for those 2 games so far. The chip is a xenium ice the dash is evox 3935. It is an early version maybe 1 or 2. All the igr's are set to off or no and i just cant figure it out. I spent all night trouble shooting it swaping hd's dvd drives chips cleaning lenses disks but to no avail. Now here is the kicker these disks have already been used in this particular xbox for over a week with no problem until monday night so let me know if you guys think of any thing thanks!

GREG