Well, if you think you may go sli/xfire in the future, then this mobo will give you x8/x8,
http://www.overclockers.co.uk/showproduct.php?prodid=MB-390-GI&groupid=701&catid=5&subcat=2261
Is there really much difference between brands, cause a lot of them seem to have the same spec, or is it mainly down to preference?
EDIT:
PS also does it matter having AMD card and a Nvidia Mobo?

Is my Mobo compatible then? ive had a quick look but i cant see what im looking for, at the moment its all a mix of numbers and letters, but im learning slowly....i think
