are you buying your 1080ti's from the american nvidia site? they are not selling them on the uk site from what I can see.
you know ive just installed ghost recon wildlands and its not playable in sli, low performance lag and stuttering and with everything maxed i only get 20fps on a 1440p gsync monitor, so ive disable SLI and wow, im going more than 70fps on extreme max settings, full AA HBOA and the new nvidia grass setting, the same with fallout for, useless on sli, but the games like gtav and primal, sli just destroys the fps, so its 50/50 with sli these days, im considering one 1080ti to start with and see how that goes, I cant stand 4k without GSync so im stuck on 1440p for now until the HDR 4k Gsync monitors come out, and still a single 1080ti might struggle on those super monitors.....
My experience is the following. I play all games at 4K.
I played the Ghost Recon beta, and SLI greatly increased my FPS. It stuttered a bit while driving, but, after lowering Level of Detail 1 notch, the game ran without stutters. However, I couldn't run the game at max settings with 2 1080s.
SLI almost doubles my FPS in Fallout 4. There are drops in big cities due to the Shadow Distance setting. These drops also happen with a single 1080. This is due to the bad graphics engine, which uses the CPU to perform shadows draw calls, causing a CPU bottleneck.
I can't max out GTA V with TXAA with 2 1080s, but SLI almost doubles my FPS. No issues whatsoever.
The same with The Witcher.
I don't own Far Cry Primal, but YouTube videos show people getting good SLI performance, so you must be doing something wrong.
https://youtu.be/QJjZxpHddSA
BF1 also scales perfectly in SLI, as well as R6S and TR.
To conclude, many games don't support SLI, but many games do.
SLI is not dead.
Of the games that don't support SLI, some can be maxed out with a single 1080 Ti (RE7, CoD IW, CoH2, maybe also GoW, etc.)
So, if you have the money, you can get a great 4K 60 FPS experience with 2 1080 Ti.
