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Is it worth getting two GTX 1070 in SLI or a single gtx 1080?

TheLegendCreator

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Feb 12, 2015
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I had my mind set on getting two GTX 1070 Founders Edition. They are cheap, they are better than a single GTX 1080, and my PC would look so good with both of them in SLI. Though, I did a bit of research on gaming performance and realized nowadays most games aren't optimized for SLI. On the other hand, my favorite games are, though: Doom, Battlefield, Battlefront, War Thunder, some Indie games like Garrys's mod fortunately, etc.

It's an unfair balance, a single card is ready for all games but if I want to SLI them for 4k then I would risk what the future of SLI holds for gaming.

PS: Intentionally, I'm planning to use both GTX 1070's at 2560x1440p and if I were to have a GTX 1080, maybe I could add a second card for 3K or 4K gaming because I think 1080 in SLI is a bit overkill for 2K (in my opinion).

Correct me in any way as possible if I'm wrong, I could take a beating.
 
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I personally wouldn't mess with SLI, the GTX 1080 is going to overpower almost everything you throw at it for 1440p and going to be good at 4k as well. Like you said not all games are optimized for SLI so most of the time you'll only be using 1 card anyway so why waste the money? I ran SLI GTX 770s for a while and overall it wasn't worth it because most of the time I was still gaming with only 1. Basically, buy 1 GTX 1080 and a sweet monitor and game your little heart out.
I personally wouldn't mess with SLI, the GTX 1080 is going to overpower almost everything you throw at it for 1440p and going to be good at 4k as well. Like you said not all games are optimized for SLI so most of the time you'll only be using 1 card anyway so why waste the money? I ran SLI GTX 770s for a while and overall it wasn't worth it because most of the time I was still gaming with only 1. Basically, buy 1 GTX 1080 and a sweet monitor and game your little heart out.
 
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Agreed sli is a huge pain. Always get a single gpu if possible. Get the gtx 1080, that way you save yourself some headache and also you have the option to add another 1080 for cheap down the road if you want more performance or if the state of sli improves
 
I am downgrading from a pair of 980 to a 1080 this weekend. 980SLI is great for games that support it, but some of the games I play now, don't. And with Nvidia disabling SLI on the 1060, and limiting the 1070 and 1080 to dual SLI I think we are seeing the last of that technology. Next gen cards are going to be faster still and make most DX11 games possible without SLI at most resolutions, and DX12 games won't use SLI or crossfire, but rather Async compute and treat all computer resources as a big pool. (Bodes well for your 1070, but by the time that is useful, there will be a single GPU that is far better)

New Unreal engine doesn't support SLI as they use a type of frame compression to avoid re-rendering the same pixels. That really is the deciding factor for me, since so many games end up with Unreal as the engine.
 
For DX12 Alternate Frame Rendering with SLI or Crossfire that is true. But the whole concept of not bothering with SLI or Crossfire and using all GPUs in a system is a core demonstration of the Ashes of Singularity everyone is using as a DX12 bench. They have shown simultaneously using AMD and Nvidia GPUs and Intel GPUs, and multiple generations of AMD cards. Haven't seen any cross model Nvidia tests, but someone has probably tested it.

Memory allocation is independent in that case as each card is rendering their own thing. Not rendering every other complete frame.

They have another version that deals with identical GPUs and that is closer to SLI and Crossfire, but still allows all the addressable memory to be pooled.

Probably more up to date information out there, but feel free to read up on the subject. http://wccftech.com/nvidia-launching-dual-gpu-flagship-graphics/
 
For the sake of all that is logical, don't bother with SLI/CF unless you're on a platform with the bandwidth and CPU PCI-E lanes required to get the most you can from multiple GPUs. X99 components have been dropping in price like crazy, and even the lowest end build will still crush any Skylake.

Anyway, my point is if you are running Z95, Z170, B150, etc., and wanting to do SLI/CF, first look up "diminishing returns, immediate and severe" and "buying two high end GPUs for my LGA115# system will result in worse performance, more trouble, and less money for things with RGB LEDs on them.
 
The single GPU consumes less power and same-ish performance. Unless your "that guy" who gets away with the electricity bill, the dual 1070's would make a killer build that looks great. What else is great is that if your the type of person that will upgrade their PC til the end of time, then a better option would be getting a 1080 and SLI that later on in your life. Otherwise, the 1080 alone isn't a bad choice.
 
I'm going to tell from my experience I've done the last 3 yrs , at first I went with a gtx 760 then went to gtx 970 by itself couldn't get my frame rate up high enough so I added another gtx 970 for sli and gotten 144 fps and gotten alittle boost on memory as well then came the gtx 1080 suppose to be as fast as 2 gtx 980s in sli and wasn't true and considering going to 2 gtx 1070s in sli for the pg279q that goes up to 165 hz but the gtx 1080 alone isn't cutting for the monitor's performance not bad if you have 60 hz 1080 p but for 1440 p 165 hz isn't good by itself unless u add another 1080 or or 1070
 
Just installed a single 1080 last night. And yes it doesn't quite compare to SLI 980s for the PG279Q, more like 1.7 980s according to the reviews. And that 165hz mode brings back all the ghosting. 144hz is more then enough. But since it is G-sync it looks pretty damn smooth about 80FPS or above. Just going to deal with it until the next generation and sell one 980 and keep one for a re-build for my brother. Or with any luck there will be a 1080Ti within three months for EVGAs step up program.

But my non-SLI titles are certainly seeing the benefits. Boosting to 2.010Ghz out of the box...

Direct comparison ignoring architecture says:

980 = 16 SM units at 128 shaders per module
1080 = 20 SM units at 128 shaders per module

EVGA SC 980 boost 1379Mhz = 1
EVGA SC 1080 boost 2010 Mhz = 1.45 * 1.25 (25% more SM units) =1.8125

So my numbers say 1.8 GTX980s without architecture improvements, so older DX11 titles will probably be about that.

To be honest at maximum graphics my 980s weren't cutting it for a lot of games as well. 2K is still a heck of a lot of pixels. I just don't want to be annoyed again by only getting to use half my graphics potential on upcoming games.