GTX 1080ti sli Low FPS, help?

[FreshBerries]

Hello, I recently upgraded to two Gtx 1080 ti's from two GTX 980's (not ti). I was really excited to run all my games at 60+ fps at 4k on ultra. Turns out something isn't going right and I am not seeing the results I had hoped, In fact in some games like watch dogs 2 and mass effect andromeda I have actually noticed a significant drop in FPS while using SLI (watch dogs 2: 45ish fps no sli, 25 fps with sli. Andromeda: 45ish fps no sli, 14-28 with sli). Initially it looked like my 2nd GPU was not being utilized, sitting at 26% according to MSI afterburner. I saw that someone else had been having a similar issue and recommended turning off G-Sync, I did that and my cards are being fully used (showing spikes up to 100% in Afterburner) but the fps is still sitting at 25 or so in Watch Dogs 2 when using SLI. 

 

Here is my build: 

Intel i7-4790k (stock speed)

Gigabyte G1 sniper M5 LGA 1150 Motherboard 

2x GTX 1080ti FE (stock speed) w/ Nvidia SLI bridge

2x 8gb of A-Data DDR3 1600mhz ram

Samsung 500gb ssd and msi 500gb ssd

Thermaltake 750w 80plus Gold PSU

Acer 4k 60hz G-Sync monitor 

 

Is my CPU bottle necking my GPUs that badly? Is my PSU not putting out enough to keep everything going? why do I get less fps while in sli? I'm at a loss here and was really hoping to see better performance than this. Is there any glaring conflict that I am not seeing? Please let me know if I can provide any other information, Thank you for any help! 

[Guest]

Maybe the game isn't optimize for SLI yet?

[Daniel Z.]

2 minutes ago, FreshBerries said:

Hello, I recently upgraded to two Gtx 1080 ti's from two GTX 980's (not ti). I was really excited to run all my games at 60+ fps at 4k on ultra. Turns out something isn't going right and I am not seeing the results I had hoped, In fact in some games like watch dogs 2 and mass effect andromeda I have actually noticed a significant drop in FPS while using SLI (watch dogs 2: 45ish fps no sli, 25 fps with sli. Andromeda: 45ish fps no sli, 14-28 with sli). Initially it looked like my 2nd GPU was not being utilized, sitting at 26% according to MSI afterburner. I saw that someone else had been having a similar issue and recommended turning off G-Sync, I did that and my cards are being fully used (showing spikes up to 100% in Afterburner) but the fps is still sitting at 25 or so in Watch Dogs 2 when using SLI. 

 

Here is my build: 

Intel i7-4790k (stock speed)

Gigabyte G1 sniper M5 LGA 1150 Motherboard 

2x GTX 1080ti FE (stock speed) w/ Nvidia SLI bridge

2x 8gb of A-Data DDR3 1600mhz ram

Samsung 500gb ssd and msi 500gb ssd

Thermaltake 750w 80plus Gold PSU

Acer 4k 60hz G-Sync monitor 

 

Is my CPU bottle necking my GPUs that badly? Is my PSU not putting out enough to keep everything going? why do I get less fps while in sli? I'm at a loss here and was really hoping to see better performance than this. Is there any glaring conflict that I am not seeing? Please let me know if I can provide any other information, Thank you for any help! 

Wow, ask nVdida support why this is happening. It could be bad SLi support

[xDylanio]

Maybe the nvidia drivers. they've been acting up for a few months now. What i did was just go back to a september driver. 

[FreshBerries]

Sorry, I forgot to mention, I had previously been using two GTX 980's in SLI and had never run into something like this. Is it possible that it would not run well for a different pair of GPU's?

 

[Masada02]

Wipe your drivers with DDU, then reinstall. If that doesn't fix it try a game that is known to have good SLI support (GTAV works really well) or a benchmarking program like Unigine Valley and see if you are getting proper scaling.

 

Edit: Regarding the drivers, Nvidia is dumb about changing cards and not reinstalling drivers. It causes issues for me all the time if I don't wipe and reinstall.

[reniat]

just spitballing, have you tried making sure both cards run fine outside of SLI? Maybe one's a dud and is holding the pair back. 

[RadiatingLight]

people like bulletbarry have been having the same issue with 1080Ti SLI.

run a single card until the issue is fixed i guess.

 

you're using the high-bandwith bridge right?

[FreshBerries]

52 minutes ago, Masada02 said:

Wipe your drivers with DDU, then reinstall. If that doesn't fix it try a game that is known to have good SLI support (GTAV works really well) or a benchmarking program like Unigine Valley and see if you are getting proper scaling.

 

Edit: Regarding the drivers, Nvidia is dumb about changing cards and not reinstalling drivers. It causes issues for me all the time if I don't wipe and reinstall.

I did this and sadly no change in watch dogs 2 (my test game). I did run firestrike ultra in SLI again and these are my results: total score 11,250. Graphics score: 12,489  graphics 1: 71, graphics 2 43, physics score 11465, physics test 36, Combined Score 6350, combined test 29.  

 

27 minutes ago, reniat said:

just spitballing, have you tried making sure both cards run fine outside of SLI? Maybe one's a dud and is holding the pair back. 

I did just try running each card individually and benched them with Firestrike ultra around 6400. So it seems that they may be fine individually. 

 

11 minutes ago, RadiatingLight said:

people like bulletbarry have been having the same issue with 1080Ti SLI.

run a single card until the issue is fixed i guess.

 

you're using the high-bandwith bridge right?

So I just watched bulletbarry's video: 

And he is describing exactly what I am experiencing. I am using the high-bandwith bridge. It kills me a little that I may have spent that much on a GPU that is best for me to not use... but like bulletbarry mentions in his video, maybe it is that the drivers still have some kinks to work out. These are the first drivers to support the 1080ti as far as I know. 

 

Bulletbarry mentions wanting to use a 1000w PSU and not seeing any improvement, am I alright with just the 750? Also, I have seen other people do benchmarks where they do show improvements with SLI, even with Watch Dogs 2.. what is the difference? https://www.youtube.com/watch?v=bzJpNh21sds 

 

Thank you for all the replies

 

[Bcat00]

Sorry to break this to you, driver support and game support isn't quite there yet for 1080ti SLI. Wait a month or two for it to smooth out because you are not the only one getting it. There's already some vidz on youtube stating this problem so just wait it out by using one gpu for now.

[Masada02]

6 hours ago, FreshBerries said:

I did this and sadly no change in watch dogs 2 (my test game). I did run firestrike ultra in SLI again and these are my results: total score 11,250. Graphics score: 12,489  graphics 1: 71, graphics 2 43, physics score 11465, physics test 36, Combined Score 6350, combined test 29.  

In that case I'd say it's definitely just lack of driver support. It will get there eventually, but it's a shame nvidia didn't have them ready for the launch of the card. 

[IceCold008]

Watchdog 2 is terrible for SLI and will bottleneck every cpu at any resolution on max settings.. Your CPU will bottleneck a very little at 4k and should NOT bottleneck for Mass effect 4. 

 

As for gync try it with and without it on. And see what happens with your FPS. But saying that g sync should only be turned off if you hitting your max FPS of your monitor due to input lag. So if you hit below 60fps at 4k, gsync should be turned on.

 

As for bottlenecks as you increase your Resolution of the game going from 1080p, to 1440p to 4k. The bottleneck should have lesser effect. Technically your CPU will bottleneck harder at 1080p and lesser at 1440p and even lesser nearly zero effect at 4k. Apart from Watchdogs 2, GTA 5, Mafia 4. All horrible games. Even 7700k overlocked to 4.9 ghz bottlenecks on them games. Cant avoid it. 

 

But again saying that 2 1080ti in sli. you should be hitting more at 4k. 

 

I myself is getting One 1080ti  for 1440p and ive seen Mass effect 4 at utlra settings on 1 1080ti at 1440p 144hz and this guy was hitting 70 to 100 fps in game all the time. And that was on a 4770k CPU the same as my own. So your 45ish. Seems just a little lower remember its 4k here. 

 

Dunno if Mass effect 4 has no SLI support "Not played it yet". I think 1080ti is a GREAT 1440P card and a OK 4k card. I still think 4k cards are still 2 generations away from being perfect.

 

 

 

[IceCold008]

Just to point out your 4790K CPU will have a lesser CPU bottleneck at 4k. Changing it will have a increase in fps but not much tbh. Not worth the money to upgrade for a few extra FPS. Unless money is no object to you.  CPU bottlenecks hit harder at lower resolutions rather than higher resolutions. 

[TizToz]

Is the 750w enough for those two cards?

[IceCold008]

5 minutes ago, TizToz said:

Is the 750w enough for those two cards?

Yea forgot about that. When i was looking for a 1080ti the recommended PSU was 600w thats for one 1080ti. His 750w is a little on the low side. A nice 1000w or 1200w PSU is recommended for SLI. Remember your hard drives, everything in your system uses power as well. You have to give yourself some headroom. Im surprised his system actually boots up LOL

[FreshBerries]

9 hours ago, Masada02 said:

In that case I'd say it's definitely just lack of driver support. It will get there eventually, but it's a shame nvidia didn't have them ready for the launch of the card. 

Thank you for the conformation, I guess I will wait and see. like you said, I'm sure it will get there eventually. I did just get dinged for a new driver update, fingers crossed! (I'm most interested in playing Mass effect andromeda and I suspect that is what the optimizations are for!)

 

7 hours ago, IceCold008 said:

Yea forgot about that. When i was looking for a 1080ti the recommended PSU was 600w thats for one 1080ti. His 750w is a little on the low side. A nice 1000w or 1200w PSU is recommended for SLI. Remember your hard drives, everything in your system uses power as well. You have to give yourself some headroom. Im surprised his system actually boots up LOL

So I haven't noticed any issues while operating (besides the seemingly low fps) I've been reading lots of different things about what I actually need for a PSU. It seems with no overclocks that my system is stable, however I may need to look into getting a 1000W in the future. I have a bitfenix phenom case so everything is pretty tight and I remember having to get a physically smaller PSU than the one I had originally planned on because of it's confined space. I haven't looked into PSU's very much, are there small form factor 1000w PSU's available? or do they all get necessarily larger with their power output?   

[Praesi]

1080Ti still has SLI Problems. In Some Games the Performance is even lower than with 1 Card.

NVidia should fix it in the near Future.

[Jayrodathome]

I'm still having this problem above. I got my two 1080tis back when they first came out. 

Timespy benchmarks are considerably higher with both enabled. 

What I do currently is dedicated the second card to physx bc if I enabled sli for Max performance with settings on auto then games run much worse than just a single card. Pub g in sli is around 60fps compared to 130 with one card. 

Rocket league is around 80fps compared to around 250 . 

Now the numbers may not seem low but there is a significant amount of frame stutter that comes with sli that makes the games unplayable. 

1300watt Corsair digital 

High bandwidth bridge 

32gb DDR 4

6700k

Dual 1tb nvme Samsung pro m.3 

I'm thinking until the bugs get fixed going to put my second one in an enclosure to use with my MacBook. 

 

Unless of course anyone has found a fix?

[qB1T]

Old ass thread but i'm having a very good experience with my games with about an 80% fps improvement (1080ti's running locked at 2050mhz). I'm running an 8700k overclocked to 4.8ghz and 32gb 3600mhz ddr4

[Mick Naughty]

Even if it wasn't a game issue, doubt that cpu would handle it. Cant even handle a pair of regular 1080's.