FPS actually LOWER with GTX 980 Ti SLI enabled! :(

[Nitruc]

I just built my PC two months ago with an i7-4790K, Asus Z97, 16 GB RAM, 1 TB HD, and Windows 10 and games installed on a 500 GB Samsung Evo SSD. My one SLI is also only two months old and the other one I just added is brand new. I even just upgraded from a Corsair RM850 to a RM1000 to make sure that I have no issues with a lack of power for these two monster cards.

But now games such as Rainbow 6: Siege, Fallout 4, and The Witcher 3 are all running at a higher and more stable FPS when I Disable SLI in the Nvidia Control Panel.

For example, Rainbow 6 detects Max Ultra settings at 3840x2160, but when I get into an actual game with SLI enabled it drops down to around 20-30 FPS and isn't playable. Disabling SLI brings it back up to around 30-60 FPS, but it's still unplayable at 4k even with turning some of the other graphics settings way down. With or without SLI, both FPS values seem very low for GTX 980 Ti cards.

What makes this issue even stranger is when I run the Heaven Benchmark on max 4K settings the FPS scores basically double when SLI is enabled through the Nvidia Control Panel... as you would expect with SLI enabled: 45.6 FPS, 1149 Score, 28.3 Min FPS, 91.9 Max FPS... So it seems like my SLI is working when benchmarking and I can see both cards are kicking at around equal power outputs, but they just don't seem to be working correctly once I get into games and SLI actually seems to be hurting my performance... My PhsyX settings are on Auto and Power Management is set to Prefer Max Performance... Heat levels seem to be fine... Tried installing the latest Nvidia drivers multiple times... nothing seems to help. I have no idea what's going on here.


Update: Watching the GPU usage for Fallout 4, it looks like when SLI is disabled my one card will use around 90% of the GPU power, as it should be doing, and reaches a nice 55-60 FPS. However, when I turn on SLI, which in theory should allow the second card to kick in to help maintain a solid 60 FPS, it's like instead both cards decide to take a break and relax around 50-70% GPU usage and together can't even hit 50 FPS.

The Witcher 3 has the same issue as Fallout, SLI causes Card 1's GPU to stay at 80-90% while Card 2 stays at 50-70% and only results in 30 FPS. Turning off SLI forces Card 1 to use 99% and Card 2 to 0%, and by having a single card at 99% I get better results at 35-40 FPS.

Rainbow 6's GPU usage is even stranger because with SLI enabled it causes one card to max out around 99% GPU and the other around 40-50%... but despite using more total GPU overall, the results are far worse than using a single card, as mentioned above.

 

[Nitruc]

Update 2: When running Heaven to benchmark, both cards are using 90%+ GPU... which explains the solid performance and noticeable difference when SLI is enabled.

Why are both my cards not using 90%+ in games?! Is there a rule I can set where it forces them to push hard in SLI until they hit 60 FPS then take a break after that? haha

 

[Nitruc]

Update 3: When running GTAV and Killing Floor 2 the cards in SLI are able to push 4k Ultra settings at 60 FPS by having both cards kick in to 70-90%+ GPU usage (which I haven't seen in other games), however, when running both GTAV and KF2 for only a minute or so, my PC begins making a high pitched alert noise. I heard this same sound when running a test last week and figured it was due to a power issue, which is why I upgraded from a RM850 to an RM1000... so now I'm also not sure what's causing this alarm... All of my monitoring stats seem normal (unless I'm missing something) as you can see here: http://oi64.tinypic.com/25gzk.jpg

What's also strange is that sometimes the GTX on the top uses more GPU and sometimes it's the opposite for different games. As you can in the screenshot, the second GTX is actually using 98% while the first is only at 93%... usually it's the opposite when testing other games.

 

[dklims]

Update 3: When running GTAV and Killing Floor 2 the cards in SLI are able to push 4k Ultra settings at 60 FPS by having both cards kick in to 70-90%+ GPU usage (which I haven't seen in other games), however, when running both GTAV and KF2 for only a minute or so, my PC begins making a high pitched alert noise. I heard this same sound when running a test last week and figured it was due to a power issue, which is why I upgraded from a RM850 to an RM1000... so now I'm also not sure what's causing this alarm... All of my monitoring stats seem normal (unless I'm missing something) as you can see here: http://oi64.tinypic.com/25gzk.jpg

What's also strange is that sometimes the GTX on the top uses more GPU and sometimes it's the opposite for different games. As you can in the screenshot, the second GTX is actually using 98% while the first is only at 93%... usually it's the opposite when testing other games.

First thing I would try is a CLEAN install of your graphics drivers.
here's a link on how. I had some serious performance issues with my 980ti's due to drivers and this usually fixed them.

http://www.tomshardware.com/faq/id-2767677/clean-graphics-driver-install-windows.html

 

[azzazel_99]

sounds like driver issues. Are you using the exact same 980ti's? Are you using the sli bridge? Also make sure the games are in full screen mode and now windowed or windowed fullscreen. SLI only works in fullscreen mode.

 

[Q8_Abdul]

I have the exact same problem. and i have a three way SLI "GTX 980 ti" , my fps is much much better when SLI is disabled than enabled as if the other 2 cards are useless when SLI is enabled, i did reseat the SLI bridge and update the drivers and the problem still exists.

It's like the SLI isn't working properly but everything is in the right place in terms of hardware, so i don't know whether it's a hardware problem or a software problem.
Apparently origin pc "Since the pc was created by them" did their benchmark ahead of sending the pc to me and their benchmark turned well "Screenshots were sent to me", when i did the same benchmark (3DMark+PCMark 8) i got a way off negative result than their's. Again i don't know what is the problem related to, is it because of my OS is Windows 10 pro and because "Origin PC" done their benchmark on my system on a Windows 8.1 pro, but again i can't relate what's causing the problem, hence all i know i have the same issue.

So Please Help !!!!!

P.S. the only game that gives me really good fps while operating on a 4k resolution and ultra settings is GTA V with minor stuttering ( 50-60 fps -> SLI Enalbed ) ( 20-30 fps -> SLI disabled )