No display after installing a new motherboard

[Suorben]

Well, a few days ago I've bought a new motherboard because I had some problems on my last one. I've installed it without any problem, put all the components back, but when I've tried to boot it I just had no signal on my monitor, even though I could hear the initial "beep" and the fans were working.
I've then put the monitor cable on the motherboard VGA to see if it would work, and yeah in this case I've got no problem, I can boot and launch windows normally.
So the next day, my dad brought the graphic card to one of his colleague to test it, he put it in his case, installed the drivers, and it worked without any problems, so the graphic card look to be working so far.
Today I have formated the computer, with the monitor joined to the motherboard, in case it was a problem of old drivers, installed the new drivers for it, put in the graphic card, joined the monitor to its DVI, but no, still not working. I really don't see what could be the problem there, the motherboard have PCI 2.0 while the graphic have PCI 2.1 but I have read that it doesn't conflict.

For the specs :
Asus M5A78L-M LX3
MSI R5850 Twin Frozr II
Windows 7

I would really appreciate some help for this, thank you in advance.


TL;DR: Graphic card working, motherboard working, but can only have a signal when connected to motherboard's VGA, not on the DVI of the graphic card.

 

[MC_K7]

Did you make sure the monitor is set to the right input? In this case DVI.

Did you connect all the required PCI-E power connectors from the PSU to the GPU?

Did you check to see if there was a BIOS update available (even though this is a new board)?

In case this is a defective port on the card, can you try with a different port depending on what's available on the card and what's available on the monitor too? Secondary DVI? VGA? HDMI? displayport?