Still not clear to me. Is there a motherboard which can support 4 x HD7950 without having to short
A1-B17 pin?
I am using Gigabyte GA 970A-D3 motherboards, has 5 PCI-E ports (one 16x, one 4x (with 16x size) and three 1x), I'm using 4 cards on this mobo, and no jumper necessary, but I'm using cablesaurus powered extender cables, they are not cheap but works perfectly.
but this is under windows 7 x64, I still haven't tested under linux, booting from USB which is my finally goal.