[SOLVED] 1 1070 GPU at 16x 3.0 or 2 1070 GPU's at 8x 3.0?

[bonhead39]

I have a few 1070's. My processor (Ryzen 7 2700x) will run one at 16x or 2 at 8x. Which would be best? I'm gaming on a 144mhz curved display.

 

[rgd1101]

what game? most game don't support sli

 

[bonhead39]

what game? most game don't support sli

I tried running two once in SLI and took a performance hit. If they weren't in SLI it did much better. I play a plethora of games and most I play supported SLI when I was running two 980ti's in SLI and of they didn't, I made them. Just overall would I'm curious to get input on if I would see performance with two 1070s at 8x or one at 16x

 

[Phaaze88]

No difference between a gpu running in x16 vs x8. The 1070 does not over-saturate either one.

I play a plethora of games and most I play supported SLI when I was running two 980ti's in SLI and of they didn't, I made them.

Multi-gpu support is limited. There's a difference between games that properly support SLI, and those that don't, whether modded or the devs running half-assed game engine patches.

What kind of temps are you seeing when both cards are running?

I'm gaming on a 144mhz curved display.

What's the resolution?

 

[bonhead39]

My resolution is 1920x1080 and GPU is running at 46c. With a 16x 3.0 running at 15760MB/s and 8x at 7880MB/s seems to me it would make a difference.

 

[Phaaze88]

GPU is running at 46c

What, on idle?
So both gpus are running at 46C max when SLI actually works in game? Are these cards liquid cooled?

With a 16x 3.0 running at 15760MB/s and 8x at 7880MB/s seems to me it would make a difference.

Nope.
https://www.gamersnexus.net/guides/2488-pci-e-3-x8-vs-x16-performance-impact-on-gpus
If a GTX 1080 doesn't fully saturate x8, then a 1070 sure won't. I believe the 2080Ti is the only one that will exceed the bandwidth of PCIE 3.0 x8.

 

[bonhead39]

Only one GPU is in right now. I just wanted to get some input before i tried the other one. 46C is what it was running at when I had SWTOR running.

 

[Phaaze88]

Well, if SLI works in the game, it doesn't hurt to just try it out.
Make sure to monitor temps of both gpus.
GTX 1070 isn't limited by x8, so no issue there. Your biggest obstacles on SLI performance are going to be temps and drivers - oh, and the power supply; but I assume you've got that area already covered.

 

[bonhead39]

So basically since the 1070 doesn't use the full bandwidth of 16x then running two at 8x would be beneficial since they utilize that bandwidth... Right?

 

[bonhead39]

Yeah I've dabbled in some mining so my PSU is overkill. Yeah I think I might as well try it out. Just wasn't 100% sure if I'd lose performance going from 16x to 8x

 

[Phaaze88]

So basically since the 1070 doesn't use the full bandwidth of 16x then running two at 8x would be beneficial since they utilize that bandwidth... Right?

That's not quite right. The bandwidth isn't added together. Same deal with how the Vram on the gpus also isn't added up.
"Since the 1070 doesn't use the full bandwidth of a single x8, it's fine to SLI them at x8/x8 with no performance loss."

The same is not true for SLI 2080Ti though. It doesn't oversaturate x16, but does(just barely) with a single x8. It's still fine to SLI at x8/x8, but there will be a minor performance loss.

Yeah I've dabbled in some mining so my PSU is overkill. Yeah I think I might as well try it out. Just wasn't 100% sure if I'd lose performance going from 16x to 8x

Nah, only if you had a 2080Ti. If I recall correctly, it uses some ~8700 MB/s of bandwidth.