Help me understand sli lanes

[wboy8807]

So I understand that sli lanes can be a maximum of 16 and if you sli 2 of the same card you have 8-8 and from what I read the performance drop in gaming is only like 1 fps. Here is the thing though. I plan on building a gaming rig with 3 980 ti in sli. that would put the lanes at 8-4-4. Does anyone know anything on what kind of performance drop this would cause? 16 lanes would also limit me on adding more things to my pcie slots correct? If I did it would likely drop even further. What advice do u have for lanes dropping 4 and lower and bottle necking in 3 way sli for gaming purposes?

 

[drtoast]

get a 4 way board with plx chips to allow 16x16 or 8x8x8x8

 

[wboy8807]

any 4 way board with plx chips will allow 8x8x8 in 3 way sli regardless of the cpu lanes? I don't know much about plx chips.

 

[someguynamedmatt]

I believe nVidia will only allow SLI to be active over eight PCIe lanes or more. Just read the specifications on the board; most high-end setups with a PLX expander will 'duplex' your total width from 16 to 32 lanes, or x8/x8/x8/x8.