Graphics Pci-e compatibility

well i have the Asus Maximus IV Gene gen 3

and a sandy bridge chip, that doesnt support PCI-E 3.0

now my question is

would having a PCI-E 3.0 card inserted into a 3.0 slot, with a chip that doesnt run 3.0 cause the card to malfunction in some way ? as it displays nothing at all when inserted into the 3.0 slot but works flawlessly in the other PCI-E slot ( that is running in X8 )

when installed into slot_0 ( the first PCI-E x16 slot ) the fans spin up, but the board shows no graphics ( it defaults to inbuilt graphics ) but installed into slot_1 i get the card to display windows

 

well ive booted up with the 750ti in the 2nd slot ( still running at X8 ) and an old 8600gt in the primary PCI-E x16 slot

the board booted perfectly into windows ( using the 750ti ) and the fan spins up on the 8600 ( meaning it HAS power ) however speccy cant see anything being connected to the slot ( it says its 'available' as opposed to 'in use'

is it a dead slot ? ( and thus ill send it back to hitman so he can attempt to RMA it ) or still incompatibility with the gen3 slot ?

 

does the 8600 work on its own in the 16x slot?

 

yeah the 8600 works just fine on its own

 

so it does sound like a compatibility issue rather than a faulty socket

 

ah i ment no card works in the X16 slot

both cards work in the X8 slot

but the X16 slot does provide power to the cards

i wonder if an X1, or and X4 card would work...dont have any to test

 

Have you tried blowing it out with air?

 

yeah ive blasted it twice with compressed air, nothing came out, and i cant see anything in the slot that shouldnt be there