XPS 730 Locking up

I have been waiting for my new xps for a while now and it finally arrived this morning. i set it up installed some stuff (firefox, itunes, g9 & g15 drivers) and some games to try it out. no first i boot up 3dmark 06 which is preinstalled and after about 30secs of bench marks it freezes. no responce from anything have to reset it. i boot up fine and just ignore it. install crysis, cod4. play about 2 mins of each the same. infact crysis froze while still in the menu not during game play. WTF right brand new gaming pc bought from dell and not home built to aviod this sort of thing. anyone have any ideas before i begin the annoying task of getting custmore support.

My exect config is
q9550 2.83ghz
2 9800gt's
4gb ddr3 1333
stock non h2c cooling
a 750gb and a 320 gb HD
using a g9 and g15 (could it be the drivers?)
fans are set to auto no overclocking or tweaking
vista home premium 32-bit
in cool room around 20c
a dell 2408 ultra sharp contected via dvi

thats about all i can think off any help will be apresiated

i tried updating all drivers and directx no luck il try a windows reinstall next. any thoughts will be apreciated

I have discovered its a problem with the second sli card and dell will replace it on monday. however my fans are stuck on full and the leds wonts light up i am also getting a ambient temperature senser unpluged or faulty during boot. THIS IS A DAY AFTER COME ON!!!!!!!!!!!! Should i wait and just tell the service man and get him to replace it or call dell again BTW the service is ok but i wouldnt call it excellet