2los,
I am working on getting this working on an A8N-SLI Premium. My first card was doa and I am getting another. Several people have gotten this setup to work on this and other SLI boards on the second PCi-e 8x slot (DFI the first slot). Basically, you have to give up SLI on these boards. These cards need a minume of 4x as stated and most boards (at least SLI boards) the 4x slot is really only two lanes. I will test it in the 4x slot but I am not hopeful that they are really 2x on these boards I believe (not sure yet).