Any fix for SLI jitters?

Sanderson · Feb 18, 2016

Any fix for SLI jitters? Months ago my SLI gtx770's were butter smooth with max settings, with horizon I'm forced to use a single GPU with most settings low.

Now with SLI I get this weird jittery "dual" effect with each GPU at about 30-40%. Any ideas?

edit: fixed by turning of shader cache in nvidia control panel (at least for me)

Sanderson · Feb 19, 2016

I should clarify:

Earlier this evening no matter what settings I set in EDH, low,medium,high or whatever, I was getting terrible "SLI jitters". I turned of shader cache in nvidia control panel and I'm now able to run on HIGH in space as opposed to max settings in days of yore. I'm very happy with that, beats jitters.

However, I do still get some jitters, occasionally, on planets and I have to reduce settings pretty close to low. Now this is weird, if I logout and reload on a planet, I can bump the settings to medium and its 75fps no jitters.

I know nothing about graphics code and all that but, as many others and I have suspected for a long long time, the shaders has a huge impact on everything, ESPECIALLY when running SLI.

All I know is that turning off the shader cache GREATLY improved my SLI experience, hopefully it will yours too.

Hooplah · Feb 19, 2016

I find that SLI has not been perfected with ED. One video card does all the processing while the other one is idle. One card seems to work a lot better than two connected but maybe I'm missing Nvidia settings others have figured out. I use SLI with audio/video Adobe products generating HD and 4K videos for professional projects which works perfect.

Sanderson · Feb 19, 2016

Hooplah said:
I find that SLI has not been perfected with ED. One video card does all the processing while the other one is idle. One card seems to work a lot better than two connected but maybe I'm missing Nvidia settings others have figured out. I use SLI with audio/video Adobe products generating HD and 4K videos for professional projects which works perfect.

My gtx770's have a load of about 35-45% (according to nvidia inspector) with max settings, the frame rate is unplayable though. At high-medium the load is the same but, smooth as silk 75fps, again according to NI. One gpu may be 35% while the other is 45%, with slight variances. Weird.

You can bet the only fix will be a new yet to be released graphics card. nVidia and AMD are smart enough not to fix the old cards lol.

tommywright · Feb 19, 2016

Yeah, I had 2x780s that ran smoothly back in the .05 SDK days but now I get that crazy judder. I swapped one out for a 970 and everything runs smooth (even a bit better than my 2x780s).

Let's face it.. Nvidia wants to sell cards so they sell us on the dream of SLI (BUY 2 and be twice as fast!!) but the reality is that SLI sucks. A 970 should never outperform 2x780s.

CylonSurfer · Feb 20, 2016

tommywright said:
Yeah, I had 2x780s that ran smoothly back in the .05 SDK days but now I get that crazy judder. I swapped one out for a 970 and everything runs smooth (even a bit better than my 2x780s).

Let's face it.. Nvidia wants to sell cards so they sell us on the dream of SLI (BUY 2 and be twice as fast!!) but the reality is that SLI sucks. A 970 should never outperform 2x780s.

Do you use SteamVR now? If you do then that is the source of your problem, E: D & Runtime 0.5 support SLI, E: D & SteamVR does not.

Running 2x GTX 980's in SLI on runtime 0.5 gives me 75FPS with eveything on high and super sampling at 1.5. 1 GTX 980 does not so SLI is certainly doing its job. Maybe not twice as fast as one card but a lot better than one card.

rich_hard1 · Feb 20, 2016

SLI or XFire is not operational in VR with Elite. Don't you guys know this already?

With my one 980ti at 2x SS I get 75fps everywhere. Just minor drops at planatary level.

Sanderson · Feb 20, 2016

rich_hard1 said:
SLI or XFire is not operational in VR with Elite. Don't you guys know this already?

With my one 980ti at 2x SS I get 75fps everywhere. Just minor drops at planatary level.

Yes it is. May have to create a custom profile but, it works.

tommywright · Feb 20, 2016

CylonSurfer said:
Do you use SteamVR now? If you do then that is the source of your problem, E: D & Runtime 0.5 support SLI, E: D & SteamVR does not.

Running 2x GTX 980's in SLI on runtime 0.5 gives me 75FPS with eveything on high and super sampling at 1.5. 1 GTX 980 does not so SLI is certainly doing its job. Maybe not twice as fast as one card but a lot better than one card.

You are correct but I can't get .05 to work (even with the switcher) so Horizons with SteamVR is the only way I can play. SLI is supported by nvidia but not by every game or app and that's my issue with it. You buy the extra card in hopes that your game supports it. Some do and some don't. Maybe SteamVR will support it one day. Until then I'll use the 970 until Pascal comes out but I will never again invest in a second card thinking it will be that much faster.

CylonSurfer · Feb 21, 2016

rich_hard1 said:
SLI or XFire is not operational in VR with Elite. Don't you guys know this already?

With my one 980ti at 2x SS I get 75fps everywhere. Just minor drops at planatary level.

SLI or XFire is not operational in ~~VR with Elite~~ SteamVR with Elite.

Fixed

Sanderson · Feb 21, 2016

CylonSurfer said:
SLI or XFire is not operational in ~~VR with Elite~~ SteamVR with Elite.

Fixed

Yes it does. Go to nVidia control panel, Manage 3D settings, find your EDH .exe (usually *:\Steam\Steamapps\Common\Elite Dangerous\Products\elite dangerous 64\ and select elite dangerous64.exe. Make sure SLI is enabled in nvidia CP and tweak setting to your desire (except AFR1 or 2 neither work) and watch your GPU loads.

I recommend turning shader cache off so ED doesn't access your HDD or SDD for them.

CylonSurfer · Feb 26, 2016

Sanderson said:
Yes it does. Go to nVidia control panel, Manage 3D settings, find your EDH .exe (usually *:\Steam\Steamapps\Common\Elite Dangerous\Products\elite dangerous 64\ and select elite dangerous64.exe. Make sure SLI is enabled in nvidia CP and tweak setting to your desire (except AFR1 or 2 neither work) and watch your GPU loads.

I recommend turning shader cache off so ED doesn't access your HDD or SDD for them.

Well I thought I'd give it a test last night and I can can say without a shadow of a doubt that SLI is not working correctly with SteamVR. After loading the game with Runtime 0.8, SteamVR and SLI enabled my game was a juddery mess ( yes, my monitor is set to 75Hz). I would estimate I achieved the same level of performance as I would with a single card while using runtime 0.5. It's certainly not worth it at all. Going from 0.5 to 0.8 + SteamVR would mean me lowering supersampling from x1.5 to x1.0. That is not going to happen while I use the DK2, I may reconsider when I have the CV1 in my hands as I hope the need for supersampling will have diminished, but I fear 2x GTX980's in SLI will still be needed to achieve 90FPS with high settings. I guess time will tell but I feel official Oculus runtime support will be required to play this game at any reasonable frame rates / settings.

Sanderson · Feb 26, 2016

CylonSurfer said:
Well I thought I'd give it a test last night and I can can say without a shadow of a doubt that SLI is not working correctly with SteamVR. After loading the game with Runtime 0.8, SteamVR and SLI enabled my game was a juddery mess ( yes, my monitor is set to 75Hz). I would estimate I achieved the same level of performance as I would with a single card while using runtime 0.5. It's certainly not worth it at all. Going from 0.5 to 0.8 + SteamVR would mean me lowering supersampling from x1.5 to x1.0. That is not going to happen while I use the DK2, I may reconsider when I have the CV1 in my hands as I hope the need for supersampling will have diminished, but I fear 2x GTX980's in SLI will still be needed to achieve 90FPS with high settings. I guess time will tell but I feel official Oculus runtime support will be required to play this game at any reasonable frame rates / settings.

Hence the title of the thread.

However, if you check your GPU usage you'll that indeed SLI is "working", although with "jitters".

CylonSurfer · Feb 26, 2016

So by extension, it's not working, the jitters are low FPS, Sli isn't really working, although granted it is enabled.

Sanderson · Feb 26, 2016

CylonSurfer said:
So by extension, it's not working, the jitters are low FPS, Sli isn't really working, although granted it is enabled.

It's not low FPS, it's related directly to the DK2. The monitor picture (using Steam VR) is butter smooth. Technically. no it's not working at 100% but, it is doing something.

prasak · Feb 27, 2016

I had SLI working on windows 7 perfectly, pity is I installed windows 10 one terrible friday night, when I got home completely drunked and my elite never worked well with 2x780s SLI since. 1 780 simply does not have power for VR in elite and SLI works using 50% of each card. I spent maybe 20 hours to make it work like it did before, nothing works. Now I am waiting for VIVE an Pascal.