I think there was a post somewhere in the ars forums where someone modded a 1x slot so it would fit.
ps. Has anyone else gotten the ex8350 to workable sustained write speeds? (50MB/s+) I'm chuggin along at 20 right now in a 4 disk RAID5 array, and while it just might barely suffice for what I'm using it for, 400$ doesnt really seem worth that performance. If I cant find any other ideas I may actually have to throw in a (gulp) windows bootdrive.