Originally posted by: batmanuel
Actually, from what I've heard, Dell used a non-standard x8 slot that is the same size as a x16 slot with half the conductors missing (unlike a real x8 which is half the length), but with some extra plastic to keep you from using their cheap server as a budget gaming box. If you are feeling lucky, it is rumored that you can cut off the extra plastic pieces and an x16 card will run in x8 mode.
Thread about modding the slot.
Sounds a bit risky, but since there are no x8 cards available the slot is pretty useless to begin with so breaking it in the process of trying to mod it really isn't going to ruin your day.