alienware d9t plz help

im trying to build a alienware d9t when i first bought it, it was for parts or repair i tried replacing the hdd which i installed a new ide drive that didnt work so i tried replacing the graphics cards and that didnt work so i tried replacing the cpu and monitor with all new inverters and that didnt work so i ended up replacing the motherboard and that didnt work either so i was able to get a refund and thats where i left the laptop for a few months until recently i purchased another motherbard from ebay and im at it again, my problem is when i power on the laptop the subwoofer makes a popping noise and theres no video on none of the graphics cards i purchased and ive tried the onboard video on a external monitor. but when i hit the power button i get a series of popping noises from the subwoofer and then after a few minutes it shuts itself off. i went on another forum asking for help and someone suggested that if the motherboard wasnt grounded it wouldnt boot up into bios or even show video??? but i found the service manual on this site for the d900t i mean it looks pretty familiar to the one i have and just looking at it i can tell i put the laptop together correctly. btw the revision of the motherboard i recenty bought was 5.3 and the cards im useing are go6800s , also the only thing i havent replaced yet is the ram but either way no ram or with ram it still doesnt show no video. if anyone can please please help me i would be very greatful

yea thats what i ended up doing ah well if i cant get it to run ill see if i can get a refund on the mb and trash the rest