SLI mode

Blestian & RedRaven, you are right. The thing is, I never told Exigeous that both cards were loaded, never said everything was flawless, etc. I do not have a cold, and I never agreed to let anyone I've only known for a month remote in to my computer to 'poke around'. I simply insisted to him that VR worked with SLI enabled - that one card was taking the load, and that it was playable. Where he got the other information is anyone's guess. Enabling SLI, and using VR works. Does it work well? I think that depends on the user, their preferences, and their system. Peace.
 
Blestian & RedRaven, you are right. The thing is, I never told Exigeous that both cards were loaded, never said everything was flawless, etc. I do not have a cold, and I never agreed to let anyone I've only known for a month remote in to my computer to 'poke around'. I simply insisted to him that VR worked with SLI enabled - that one card was taking the load, and that it was playable. Where he got the other information is anyone's guess. Enabling SLI, and using VR works. Does it work well? I think that depends on the user, their preferences, and their system. Peace.

No worries mate - I think the main thing is - if you're happy with the experience, it doesn't break the bank, and you enjoy the in-the-game immersion in ED etc, it doesn't really matter.

What matters is your enjoyment :)

PS: even if it does break the bank, if you can get it past the missus... :D
 
Blestian & RedRaven, you are right. The thing is, I never told Exigeous that both cards were loaded, never said everything was flawless, etc. I do not have a cold, and I never agreed to let anyone I've only known for a month remote in to my computer to 'poke around'. I simply insisted to him that VR worked with SLI enabled - that one card was taking the load, and that it was playable. Where he got the other information is anyone's guess. Enabling SLI, and using VR works. Does it work well? I think that depends on the user, their preferences, and their system. Peace.

Not to argue Nacho but I definitely remember our first conversation very differently. I don't at all remember you saying anything like "it's enabled but it's only using one card" - as Metsys and I asked a ton of questions you insisted that SLI was running and it was using it. That said it really doesn't matter, as has been said if you're enjoying it that's all that really matters. The reason Metsys and I were having a hard time understanding what was going on as we've both tried SLI in VR with either no benefit or in my case horrible ghosting making it unplayable. I'm also sorry you misunderstood what I wanted to see - I didn't at all mean to say or imply that I wanted to get on your machine, what I think I said and should have been more clear about was setting up some kind of live stream so we could see the settings and the performance counters that you put in the video - which also works just fine.

At the end of the day it sorta seems we're right - clearly you have SLI enabled and only clearly it's not being used by either Elite or Project Cars. It's great that at least it's not causing you problems like it does many who try (specifically ghosting), my gut says something in the OSVR driver/api it's either hard coded to use a specific GPU or to just ignore one of the cards while in SLI. I do hope in the future SLI gets to the point where we can have 1 GPU per eye but that's likely a ways out and as cards get faster and faster it won't be necessary. Going from my SLI Titan Z to a single 1080 was a huge boost in performance without any SLI headaches and very limited SLI support.

Again all that matters is that you're pleased with the performance you get - clearly that's the case which is great. I would be curious of a few other things:

- What frame rate are you getting in Elite and/or Project Cars with SLI enabled?
- What frame rate are you getting without SLI enabled?
- Do you have non-VR games that support SLI? It would be interesting to see the performance graphs from Afterburner to see the load on each GPU
- Have you ever looked at the PhysX settings? Is it set to manual or a specific GPU? If that's true that could explain a few things like why the load on the 2nd card is so low since Elite or Project Cars neither support PhysX (at least I don't think so)

Of course none of this is a big deal, just my inner dork wondering what's happening.

~X
 
Blestian & RedRaven, you are right. The thing is, I never told Exigeous that both cards were loaded, never said everything was flawless, etc. I do not have a cold, and I never agreed to let anyone I've only known for a month remote in to my computer to 'poke around'. I simply insisted to him that VR worked with SLI enabled - that one card was taking the load, and that it was playable. Where he got the other information is anyone's guess. Enabling SLI, and using VR works. Does it work well? I think that depends on the user, their preferences, and their system. Peace.

There is a big difference in a VR title tolerating a second card being attached and what one would consider "working" Unless one can demonstrate a framerate increase that proves sli is being taken advantage it would have been prudent to avoid suggesting sli "works" in vr.

I am glad to see your attempt to clarify what you say you meant, so that some new vr users don't go out and buy a 2nd card, hoping to see SLI type improvements as not only is not supported-it doesn't "work".
 
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Thank you for the video. You might have SLI enabled with no issues but its certainly not sharing the rendering so it deos NOT 'work' in SLI.
 
EX, I forgot to mention that one card for each eye is already available. Nvidia VRWorks is the API(?) for this, game developers are the ones that have to integrate it into their programs. I am not sure how it works, but it is supposed to dedicated one GPU per eye. Nvidia VR Funhouse supposedly uses SLI, so the tech exists. https://blogs.nvidia.com/blog/2016/07/14/vr-funhouse-advanced-vr-game/ I have not tried it, but might in the future to see.

https://developer.nvidia.com/vrworks

VR SLI, as it is called, requires implementation by both Oculus et al and Frontier and dx12 to be fully functional, (although has some partial support in dx11) before it will work in ED. Would not count on it happening too soon as we VR users are a small installed base right now. I doubt Ed will move to dx12 very soon.
 
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I also came across this post:

https://www.reddit.com/r/oculus/comments/41ui09/windows_10_sli_dk2_and_elite_dangerous/

I've been struggling for months now to get Elite working in VR again on windows 10. I've finally found a way that works that some might find acceptable/useful.

Essentially the problems for me began when windows switched from it's WDDM 1.3 to WDDM 2.0 which gives access to the (forthcoming) features of DX12. Upgrading to the WDDM 2.0 enabled driver sets has broken rift usage for me in windows 10 whilst using SLI.

A lot of people seem to think SLI doesn't work with the rift - but for me its the difference between mostly stable when active 75fps and not anywhere near that when switched off. I honestly don't notice any latency and this is in a 3 way 760 SLI setup. (I won the third card in a competition - with some poetry I might add! - before you flame me for the build xD)

I struggled in vain for ages trying to get the runtime switcher to work but even when it switched to 0.5 (steamvr doesn't support/use SLI for me) it would crash my PC. I literally thought I had a hardware issue with my GPUs.

However today it dawned on me the problems began with the DX12 driver branch so I went back and re-installed 347.88 enabled the runtime switcher to 0.5 and now SLI functionality has returned and works flawlessly!

I realise this won't be an acceptable solution for some who need the most up to date drivers for more recent games but I really only play Elite in VR and DOTA 2. So I'm super happy! :D
 
Once again for the non-believers - https://drive.google.com/file/d/0B0HcYHil5jc_bjBTVzVqN1Nrb3M/view?usp=sharing

I would also like to add, as many here are aware, that 'support' in a product differs from 'working'. Support in this case means that Nvidia, Steam, Occulus, game developers, etc., are not officially stating that their software or products will work in VR with SLI. This means results can vary from user to user, and they are not responsible for technically supporting it. This appears to be the case here, as I also have a close friend with 2x980's, SLI enabled, whose Occulus DOES work with SLI enabled (although he has tracking issues). I helped him set it up.

Fascinating but I don't want another card.
 
Fascinating but I don't want another card.


Nothing fascinating about it. Look at the GPU 1 load - there isn't any. Only one card is loaded. The SLI option is simply enabled in the driver, that doesnt mean SLI is actually being used. Not sure why people are thinking this implies SLI works.
 
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I'm just going to try and revive this thread.
There are reports of people having full/almost full utilization from SLI in VR when playing ED.

https://forums.oculus.com/vip/discussion/40007/elite-dangerous-and-sli-2-x-970

Seems convincing to me.
Although I would like to have some more people with SLI and Oculus CV1 test it before I go and buy another card.

I think the main confusion people are having is VR users don't want standard sli support but VRSLI support. Below is quote from nvidia website explaining the difference.

"However, to ensure the ultimate experience with rock solid framerates, which is crucial for avoiding eye strain and jarring frame drops, a fast SLI configuration is recommended. In traditional games SLI doubles performance, letting you play at higher resolutions and with more eye candy. In VR games, SLI rendering introduces a frame of latency, which is the antithesis of our work mentioned earlier. To avoid this frame of latency we have developed "VR SLI", which has each GPU output to a separate eye in a VR headset. This allows games to fully utilize both GPUs in parallel, and increase delivered frame rates."

Source http://www.geforce.com/whats-new/articles/maxwell-architecture-gtx-980-970
 
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