Is SLI a scam?

RAM does not add. Yi still have 11 GB of RAM tho each is "painting" a different part of your screen.

SLI has been great and bad for nVidia for a number of years. While its a great way to increase performance when no other options exist, it drove nVidia crazy because it loses them money ... they make more money selling a 980 than two 970s for the same price. Up through the 9xx series, SLI, at least 2 way SLI was a no brainer.... 40% more performance for the same price. And yes, that includes the games that didn't provide support or had poor scaling. And as annoying as that was to lose all those first tier sales, nVidia had to keep up performnce or AMD would have an edge.

But then one big thing and a couple of small things happened and that something was AMD dropped the ball. AMD had no answer to the 9xx series. nVidia sold more 970s, more than 2 times more 97s than AMD sold all of the entire 2xx and 3xx cards combined. As the 1xxx series was about to drop, and again no competition at the top end from AMD, nVidia dropped official support down to 2 cards.

The other thing that happened, again sparked by lack of competition fro AMD was that the price difference between the 1070 and 1080 dropped. You could no longer buy 2 x70s for the price of a x80.. And finally, something **funny** happened to SLI, where scaling was pretty consistent at just about 70% regardless of resolution, everything went whacky w/ 10xx series.

1080p scaling was just 18%
1440pp scaling was just 33%
2160p scaling was over 50%

What the hey ? technically this doesn't make sense. But financially it does ... at 1080p
a) Ya can get an 18% performance increase by spending 21 % more for a 1080, or
b) Ya can get an 18% performance increase by spending 65 % more for (2) 1070s

Customer makes the obvious choice, nVidia makes more moeny selling the 1 card

At 1440p

a) Ya can get an 61% performance increase by spending 66 % more for a 1080 TI, or
b) Ya can get an 33% performance increase by spending 65 % more for (2) 1070s

At 2160p

a) Ya can get an 66% performance increase by spending 66 % more for a 1080 TI, or
b) Ya can get an 54% performance increase by spending 65 % more for (2) 1070s

Here's it not so bad and why make it even close to competitive ... because one 1080 Ti just doesn't cut it at 2160p and peeps want want more will put twin 1080 Ti's in to get more performance.

Now 3 way SLI doesn't give you and never has given you the scaling that 2 way does

We can see that SLI matters at 2160p as it takes RoTR from 58.2 to 111.8 fps ... 98% scaling ? yeah Im in ! Once the 144 Hz screens drop 1Q 2018, I expect we will see this bump up a bit. But that's the best ya gonan see

Lower budget games were never big on SLI and they didn't need to be ... when ya already getting 70 fps, what good really is getting 110 ? It as the demanding games that gave SLI a role to play and until 4k becomes

AMD doesn't have a single card in the top 20 with regard to gamer market sage, their top entry at 23 is a "series" of cards. Until AMD gets some competition going, improving SLI performance is the last thing they want to do. All it would do is reduce sales on their most profitable cards. I can only recommend it at 4k and I can't recommend 4k at this time.

as to 3 way, I just can't make a case for it ant any time, even back when 2 made perfect sense

https://us.hardware.info/reviews/6292/17/nvidia-geforce-gtx-980-ti-sli--3-way-sli--4-way-sli-review-ultra-hd-in-ultra-quality-conclusion