Yeah i have settled to run my SLI in the slots 1 and 4. Works without problem. It's also the way this board is meant to be used for SLI, as we get x16 x16 that way. For TRI SLI, we must use slots 1, 2 and 4.
I wonder wha is the use for the slot # 3 ? I cant be used for TRI SLI, cause the slot 2 will block the slot 3. It cant be used for 2-way SLI either, cause well, it's just not working and it wont recognize the GPU for SLI.
I would return it, and get a Rampage black edition that will soon come out, but i would probably have to eat a 15% restocking fee from newegg. The board is actually working as it should as far as i can see from my research on the web.
By the way, I really like ASUS, they make the best overall motherboard in my opnion, but their tech support is pretty bad (by email). They take like 24 hours+ to reply, sometimes up to 48 hours, and they don't seem to know their hardware specification very well. (I should probably call them but i'm shy and my english is not the best, not my native language).