Crash to desktop when going full screen

[Dizzydan02]

my desktop is 3.2 extreme, 1gig memory, 6800 ultra video card
my laptop is 3.6, 1gig ddr2, 6800 ultra pciexpress

when i go to windowed mode or full screen on my desktop it does just fine, but when i do it on my laptop my game closes altogether....so i dont know what the deal is, my drivers are all up to date.