980 Sli dedicated a card to physX runs on high

[BodyPolitic]

So just like the reccomend says, I dedicated one of my cards to PhysX in Nvidia control panel.
Its worth noting this is a global change, so be sure to change it back once through unless your'e only going to play Arkham Knight as your other game

Performance wise, selected high, and benched at 90 no problems there. Kept up looked gorgueous especially the wack a mole hair.

Then as an experiment I removed the physX dedication and set my system back to sli. Went into the game selected high at it "looked" like it took it, but when playing noticed it was doing physic actions at the equivelent of low. This doesn't effect clarity or shiniess, but things like how many particles fill the air when popping balloons, hair quality, how thngs break etc. It ran fine but definitly seemed to be lower vs, running on high w/ a card dedicated.

FWiW I attempted to overload my cards during the baloon popping by putting as many particles in the air as possible and I do think it mad some minor slow down when it was ridiculous particles every where.


All in all neat little demo, setup as mini carnival games where its tmed and a score is kept. Nice for proof of concept but I think I'll keep my cards in sli configuration for normal play. One very strange quirk, it loaded with no sound. I switch to a secondary audio source when using the vive as my primary headset is in short usb leash. I've had this happen rarely with other VR titles. If you have multi gpu setups definitly reccomend dedicating 1 card to PhysX and I believe it will run on much lower HW than Nvidia reccomends

[BodyPolitic]

Okay,
Second time through, got the sound issues sorted (just a restart)

Things of note:
Shoot the water/goo gun at your face, it will splat and stick, and you can shake your head to clear it !

Baloon popping, was impressed that you can wave the blade around in the air, and it realisticly models changes in air current causing vortexes and eddies.

Shooting the gun in cannon skeet, the smoke that forms at end of the barrel is tinted Nvidia green. Also these are some extra dimensional six shooters as they never ran out of rounds.

Also noted at the end, there where 2 or 3 more games noted as coming soon, so I completly expect this to be updated.

Rated 7/10
I would like to see the hair works from the punch a dummy game implemented into a VR boxing game, seeing thier hair shake was rather satisfying when you punch them

[JudgeTy]

Thanks for posting! Good info!

I have a 1080 gtx se oc and a spare 970 gtx se oc, only have a 650 watt psu though, I've never messed with SLI or dual card configs, trying to figure if its 1) possible and 2) worth me buying a power cable adapter to *attempt* to run a 1080 and 970 (just physX enabled).

[pittsburghjoe]

how do you know the second 980 was being used at all ..when not used as a physx card?

[JudgeTy]

The 980 is only being used for a physics card. Only on some rare directx 12 setting will a hybrid combo of graphics cards be used. (As far as I know this is still theoretical, and yet to be tested/implemented)

EDIT: For dual 980 sli this has to be enabled by devs in the program, and VR doesn't necessarily take full advantage of SLI as far as I know. Some heavy physX games would stand better have a card used as full physX versus SLI.

[BodyPolitic]

Originally posted by pittsburghjoe:

how do you know the second 980 was being used at all ..when not used as a physx card?

In this case, I set it specifically to use as a physx card in control panel and I know its being used because VR funhouse is a PhysX demo

[pittsburghjoe]

I'm trying to find out if 980 sli ..one card per eye ..is working with funhouse. Or if the 1000 series (pascal) is even doing that

[BodyPolitic]

Originally posted by Ben Burris:

The 980 is only being used for a physics card. Only on some rare directx 12 setting will a hybrid combo of graphics cards be used. (As far as I know this is still theoretical, and yet to be tested/implemented)

EDIT: For dual 980 sli this has to be enabled by devs in the program, and VR doesn't necessarily take full advantage of SLI as far as I know. Some heavy physX games would stand better have a card used as full physX versus SLI.

This setup I implemented dedicating 1 980 to physx isn't something I would normally ever run, only did it for the VR Fun house, and quickly switched it back after ward.

Normally I won't bother with a dedicated physX card since I only have 2 980's, if I had a 3rd card in the box like a 770, I'd dedicate that to PhysX and keep my sli 980s for mgpu use.

You are correct that sli is pretty rare in VR, but both Nvidia and SteamVR offer the capability for utilizing it, in a dedicate 1 card per eye setup that allows for the low latency needed by VR. So its not the regular alternate frame render method of sli, but it does exist. I only know of a few VR programs that use it so far, Nviidia Funhouse, and Polynomial 2 both use it.


And to the question asker before. how do you know its working? (I will take a log of gpu utilization for both cards in gpu z so you can see if the second is being used or not, its pretty apparent one way or the other

[pittsburghjoe]

I'll eat my shoe if Polynomial 2 has vrworks setup for one card per eye. Main branches of Unity and UE4 don't even have it figured out yet.

[BodyPolitic]

Originally posted by pittsburghjoe:

I'll eat my shoe if Polynomial 2 has vrworks setup for one card per eye. Main branches of Unity and UE4 don't even have it figured out yet.

It may not be doing 1 eye per card, I just noticed its utilizging both cards, so no sure whats going on

[jason.washdc]

Originally posted by pittsburghjoe:

I'm trying to find out if 980 sli ..one card per eye ..is working with funhouse. Or if the 1000 series (pascal) is even doing that

I read somewhere on Nvidia's site that SLI is only enabled if there is a third GPU dedicated to PhysX. I have 980 Ti's and get same results with SLI enabled or disabled. The Star Wars experience that came out today is the first time I have seen SLI work in VR for me.

[pittsburghjoe]

well, that's embarrassing for Nvidia. Thanks Jason

[[TC] SirLamer]

Actually the prevalence of PhysX in VR games is much more common than in the general market on account of many games involving direct physical interaction with objects. I have a GTX 1080 as my main card for rendering and my old GTX 780 for dedicated PhysX and it works well. Even Job Simulator runs on PhysX.

Note I am not saying "I notice a huge difference in performance", but what I have for a set up works fine. I have to think that the only benefit would be realized during burst physics loads so that the video rendering GPU doesn't drop frames. This would probably not reflect in performance benchmark scoring tests and stuff.

What I really wan to see is CUDA on a dedicated GPU for the benefit of games with procedural environment generation like Elite Dangerous. There is going to be more and more of that coming.

[craigh95630]

I just got a 1070, and will be setting up my 970 to use as a PhysX card. The general consensus was that this is a waste of power and generates extra heat for the limited number of games that use it. However I think that we will see a resurgence of PhysX because of VR.

[jason.washdc]

Originally posted by craigh95630:

I just got a 1070, and will be setting up my 970 to use as a PhysX card. The general consensus was that this is a waste of power and generates extra heat for the limited number of games that use it. However I think that we will see a resurgence of PhysX because of VR.

I think you made a good choice. It is not like that 970 is going to generate a ton of heat.

[BodyPolitic]

Finally got an update from the Raw Data guys, they currently are not utilizing per eye sli, they say get epic to implement it into main branch of UE4 and they'd consider.

They ARE using PhysX, (here it gets a bit shaky) says they have it set to utilize the cpu and didn't know if a dedicated card would affect performance.