Sli does not seem to be utilized properly

[Blazza]

I saw a very small note on some very random page (written by SE at least) that SLI will be supported on release, meaning it's not supported now. My system is the same as yours but 670s instead of 680s, ran fine throughout beta phase 3, but had a lot of fps issues in phase 4. Also had a fairly regular black screen of death every few hours where everything died except for the bgm, my monitors even switched off and the only way out of it was to hard reset my comp. Having a heap of characters on screen at once certainly did hinder performance, but I also had other poor performance at seemingly random times, nothing I could see in game that should have been causing that sort of slow down. One other thing that reduced my fps from ~60 to ~14 was the end portal in copperbell mines, depending on whether or not it was on screen.

I should probably also mention that I'm running 3 monitors.

Edit: I should probably also add that I'm still waiting on my early access code, so this is going off phase 4 beta.
Aaaand also I should add that installing the latest Nvidia beta driver did help somewhat.