Screen won´t turn on

Hello,

Recently I've bought a new case for my computer, I´ve installed all the parts in the new casing, I did everything very carefully I wanted to make sure I wouldn't mess anything up.
As soon as I turn my computer on everything makes the right grumbling sound, everything is runnin' 'n spinnin' as its supposed to be. But neither of the screens will turn on.
I´m so sure I did everything right I've re-installed everything about 4 times.
Everything appears to be running, the green light on the MB is glowing, I've tested my video card on another computer and it worked. Tested both of the screens on a other computer and it worked.
The led light under the power button off the screen stays Orange, it always turns blue when it activates.
The screen just stays black.

I've even tried connecting everything and turning it on without the casing, its really driving me nutts usually I never really turn to forums since I'm usually always able to fix stuff myself.
But I hope anyone who may has experienced this before can help me

My Specs:
Nvidia 8800GT
Intel Q6600
4 x 2 DDR2 RAM
Fujitsu "22 flatscreen & LG 20" flatscreen
Asus PQL-E MB




Cheers,

Leroy (:

I've tried both cables in both ports, and I did get the message once "no signal".

Well, I plugged the 8800 in my dual core computer in the living room and tested both of the screens, they directly turned on.

Hey thanks for the help anyway, I never re-attached the speaker and I did so I listened for the beep amounts and noticed I was getting one long beep 4 fast beeps then one seperated beep again.

I googled it and it says it means my motherboard is bad..
I guess something wrong happened to my motherboard by heck I have no idea how I did everything right.
I guess I'll have to get a new one even tho I got this one for about 3 weeks now.

Thanks again Matronix (:

Leroy