???? cant say I'd just use the bridge that came with the motherboard unless I go that 4/5 k thing they claim it benefits in that and really seen that need for it .
then again to me anymore SLI means S-udden L-oss of I-ncome
and now how NVidia is jacking around with it and as well as developers makes it to me less value [opinion] just one strong 1080 should run all you need fine
no heat issue ,no power issue ,no driver issues, no maintainance overhead, finding most games may not be optimized for sli so you got 2x the money and find headach and 1/2 what you want may not utilize it .
don't get me wrong I did a sli rig ''once'' and after that never thought to ever go back to one [more opinion]
good luck