Build advice (potential 1080ti SLI)

[Qebm]

Hi! I could use some advice for my setup(s).
I just moved to a new house, and currently I have:
- one pc at my desk, with i7-6700k and 1080ti, with two 27" 1440p displays, for 5-boxing WoW w/IsBoxer, graphic/multimedia/productivity softwares, and other games more suited for keyboard and mouse;
- another pc, with i7-4790k and, another 1080ti, connected to a 4k TV on the living room, for "gamepad&sofa" games
- a j1900 "home server"/download station.
Both gaming pcs are to be watercooled.

Now I've just found out about nVidia GFE Game Streaming/Moonlight, so I'm thinking it would be more rational to have just one powerful pc, and have it stream 4k games to a HTPC in the living room (don't know if a J4205 or the oncoming J5005 would be powerful enough to be a client; a i3 "T" could also be an option).
My first thought was to put both 1080ti in SLI (although SLI support is a gamble, I know), and now I'm wondering if I should move to another chipset for a 6/8/10 cores CPU. I was almost ready to buy an i9-7900x (850 euros, plus 250-350 for the motherboard :P), then I read mixed reviews about it, so I'm here to ask you

[Qebm]

So, I've read a bit in the meantime, and I'm reconsidering again. I think I'll ditch the SLI idea, and settle down for a 6-8 core cpu, so I'm torn between the i7-8700k and the Ryzen 7 1800x. Any advice? Thanks!

[driftz]

I'm running 8 accounts, they are all running at 60 fps in background at low settings. I have an 8700k with 32b of ram, could probably turn the graphics up if I had a 1080ti. I am running an asrock z370 gaming k6 motherboard which was only 170 bucks.

[Qebm]

Thanks for sharing! I eventually opted for the 8700k (not having to buy another waterblock was a nice bonus) paired with a MSI Z370 Gaming Pro Carbon.