PCI-E problem, reducing speeds

[HKH]

I have some weird problems with my motherboard

Here is my computer spec

i7 930
6gb 1600 Ram
480 GTX
DFI T3H6 (x16/x16 PCI-E xifre/sli)

Ok here is the problem
I was using 2x5850 and the computer ran fine with x16/x16 speeds
But yesterday when I changed to a 480GTX, both slots ran fine with x16/x16
But I rebooted and suddenly the first slot PCI-E ran with x1 speeds
I rebooted and the same slot ran with x8 speeds
No matter how many times I reboot, the motherboard keeps running the card at x1 or x8
The other slot works fine, always x16, which I am using now
I am 100% sure the Motherboard is supposed to run both at x16
The bios is at default except for the 4ghz overclock with a 1.285 vcore adjustment
Is there anyway to force the PCI-E to run at x16?

Is my PCI-E slot broken?
I want to SLi another 480 later, but I can afford it to run at x8 speeds =.=

Thank you for all the help

 

[Maziar]

Revert your OC to normal speed and clear CMOS,and see if it helps.
Also try using the latest BIOS for your motherboard.
And which software do you use to check your PCI-E speed? GPU-Z ?

 

[HKH]

Revert your OC to normal speed and clear CMOS,and see if it helps.
Also try using the latest BIOS for your motherboard.
And which software do you use to check your PCI-E speed? GPU-Z ?

Yes GPU-Z and I am sure the readings are correct, because I am getting 60fps compared to 140+ normally
I'll try with the CMOS thing

 

[nukemaster]

Remove and reinsert the card a few times. I have seen dirt on the contacts(my guess for you) or a card that is not pushed in all the way cause this issue.