hrmm.. well it looks like xs has also found some falsely advertised things on ebay.. and they're curious as well....
here's their take on it here
Is this even possible? Quad 8800 SLI? - Page 2 - XtremeSystems Forums
and i don't know how to quote but i'll quote someone from there...
"Not only 680a, but this 680i as well...
With dual northbridges instead of northbridge/southbridge, it's got the support for 4xSLi. I gave it to the kids though, I hate nVidia pretty much now..."
"here are the links to the old quad sli and some explanation how it functions:
to summ up, in both generations of the X2 cards an internal PCIe switch via which they are interconnected. and the older generation (7900X2)cards also have an internal SLI bridge. so in theory the gpus could be interconnected via pcie slots (gpu1 to GPU2, GPU3 to GPU4, GPU1 to GPU3) and additionally, as i earlier described, via pcie slots (like the 7900X2 cards).
and since the guy put up a Quad 8800 gt rig, i believe he is using 2 long flexible sli bridges to connect GPU1 to 3 and 2 to 4 (you'd have to twist the sli bridge though), and the rest of the daata is transfered via PCIe bus. (so in this case that would be like mimmicking the behaviour of the newer 7950X2 cards which do not have an internal sli bridge to connect GPU 1 to 2, and 3 to 4)"
hrmmm wondering.... i'm very curious to see someone try this out