Nvidia SLI - Possible big framerate improvement.

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EDIT: Does not always appear to work for multiview setups!
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My framerate at Silverstone just went from average 55fps to 100fps with one setting change (SLI compatibility bits). This is with everything set to max (including both reflection settings) and using Level 4 AA + 4x SparseGrid Supersampling.

Obviously I can't guarantee it will work for others but I thought I should at least post it. I am using a 690 GTX but I think the setting should work for other SLI setups too. Also apologies if the same thing has already been mentioned here - I haven't been able to read the forum much for the past couple of weeks.

First of all you will need Nvidia Inspector to try this setting AND you must set your main Antialiasing through the rFactor 2 config program. This is important - the new SLI compatibility bits setting doesn't seem to make any difference if you use Inspector or Nvidia Control Panel to apply your main AA. You can however use Inspector to apply SparseGrid Supersampling, on top of whatever AA Level you selected in the rFactor 2 config.

These are my settings (I will attach a pic of my Inspector setup too),

rFactor 2 config - Level 4 AA selected.

Nvidia Inspector settings,
'Antialiasing Mode' and 'Antialiasing Setting' should be set to 'Application Controlled'.
'Antialiasing - Transparency Mulitsampling' - I have this set to 'Enabled', but you don't have to use this.
'Antialiasing - Transparency Supersampling' - This is where you can set your Sparse Grid setting if you want it.
'Antialiasing - SLI AA' - this is worth enabling if you haven't used it before. It can improve AA performance with SLI setups.

Apart from that you just need to change your 'SLI compatibility bits' to 0x00500005 - this is the change that gave me the big improvement.

I had previously used the rFactor 2 default setting for this which is 0x02402005, and more recently I was using 0x82482005 (this had been recommended on this forum in the past). With the new setting (which it says is for the 'Windows System Assessment Tool') I have almost doubled my framerate on Silverstone.

NOTE - I haven't tested this setting on Feels3 tracks, but I have noticed that sometimes when an AA setting improves performance on ISI tracks it can sometimes decrease performance on Feels3 tracks (and vice versa), so be aware of that.

Thanks for listening!

 

Good find here mate, where did you find that bit? All previous combat bits i used caused flickering textures when enabling SLI with rF2, hence i didn't like Inspector. Also like you 690 here and have had a fairly large boost using this, enough now that i can add 8xSGSS and it still maintains fps i want. This is better than i had with my combo. Very good work. I'm interested to see if this works with others setups.

 

There's been several posts about compatibility bits - but no harm mentioning it again

 

Previous combat bits caused more problems than good though for me. As said i had really annoying flickering with any previous settings. This though is perfect, by far the best rF2 has run on my rig with this setup. Was happy already but this has boosted a fair bit. Not seen this line suggested before.

All good now, just hope there is not a draw back round the corner. Had flickering with others, these seem too perfect right now, something has to rear it's head surely. And they are meant for the Windows System Assessment Tool, quite odd but it really does work.

Drivers used 326.01

Maybe a good idea to ask Tim to sticky this thread

 

I actually found it while reading the GeForce SLI support forums. I found a post there that was made a couple of weeks ago about rFactor2 - it doesn't have any replies as I guess the sim is not mainstream enough, but credit goes to the guy who made this post...

https://forums.geforce.com/default/topic/549161/sli/rfactor-2-sli-profile/

Originally it made no difference to my framerate, but I was using Nvidia Control Panel for my main AA as well - I did some more testing and realised that I needed to apply AA through the rFactor 2 Config program for this new Bits setting to work.

The GeForce forum post also mentions an 'AA bits' setting of 0x000000C0 but I tried that in both 'Antialiasing Behavior' and 'Antialiasing Compatibility' and I didn't notice any difference (in framerate or AA quality).

I was hovering around the 55fps mark at Silverstone (alone on track) while using 2xSparseGrid. Now I can use 4x SparseGrid and have around 100fps, so it's made a massive difference.

I'm glad it has helped you too.

 

I'm sorry - I misunderstood ... sounds like an excellent new "bits" setting. Yes, please sticky this Tim!

 

Forthright - what are tulhe specs of your machine, what cars are you running and what resolution?

 

I assume he is at 1080p like me as he has the same card (690)and i have basically the same FPS as he mentioned. In pit of Silverstone with these settings i have 110fps game maxed with rF2 AA. Add 8XSGAA i am still well over 60fps in pits. So while i already had decent fps with my previous settings, i never had enough to afford SGAA on top and still be happy. I had multi GPU AA @ 8. As said this now affords me the SGAA setting if needed and still maintain above 60fps.

If i renember rightly you have 680 SLI which going on benchmarks is normally around 3fps faster than a 690, so you should see the same sort of boosts. Although not as much due to triples that you use. It should allow you to turn some candy back on elsewhere though in sim.

Great find and yes i think Tim should Sticky this. Could help alot of SLI owner get the best from their setups

Thanks Fortright!

 

Something for me to try out!

 

For me, grid of 20 Nissan GT-R cars and with me at the back I start at 59fps and that rises to 109FPS on Hangar Straight on first lap. This is at 5760 x 1080. This is using the older compatibility bits setting though.

 

Monitor is 1080p but it's 120Hz so the more fps the better.

My testing has all been alone on track, but on my system adding AI cars doesn't cause massive drops - for example I know if I'm getting 100fps alone on track I shouldn't drop much below 60fps at the back of a big grid.

Full specs,
3570k @ 4.2Ghz
8GB 1600 DDR3 Ram
GTX 690
rFactor 2 installed on SSD drive

 

It will be intesting to see if this perfomance increase carries over to SLI surround and will allow me to run HDR + MultiView wiht good framerate. I won't be able to test this for 6 or 7 hours though...

 

I will test out later today too and see if there is a gain for me. Thanks again guys!

 

I don't understand if this nvidia inspector overrides nvidia control panel settings? Should I reset my rF2 profile in control panel and only use inspector?

That's what I did. I'm lost in all the different settings in inspector, but I did enable the 'important' stuff for performance increase, and for me it's not working. +90 fps alone on track, but only 45 with 20 Nissan GTR on the grid.

This gave me improvement, from 70 to +90 fps alone on track, but on the grid with 20 AI's it's the exactly same as before (45).

This was enabled by default. But as it seems I could rather use it from nvidia control panel, it gave me pretty much same results. But maybe I'm doing something wrong. I'll do some more testings.

 

I can only assume that with 20 AI cars you are being bottlenecked by the CPU, not sure though.

 

Good question.

I've never set up a profile for rFactor2 in the normal Control Panel settings so I can't answer this.

Control Panel and Inspector are pretty much 'the same thing' when you're changing the Global Settings - if you change a setting in Nvidia Control Panel's Global settings and then check Inspector's Global settings the same change will also have been made there. When it comes to game profiles though I'm not sure - for example, I have an rFactor 2 profile in Inspector (everyone should as it comes with the drivers) but I don't have an rFactor 2 profile in basic Nvidia Control Panel (I think I would have to make one myself). So I'm not sure how they will work with each other if you have a profile for the same game in both programs.

My head hurts just thinking about it..

 

I decided to try this myself so I just did the standard 'back of a 20 car grid' test with my old settings and with the new settings listed in my first post. There was still a definite improvement but not as much as being alone on track.

Back of 20 car grid with old settings - 44fps
Back of 20 car grid with new settings - 67fps

So there was still over 20fps increase even with the AI in front of me.

I would suggest deleting your rFactor 2 profile from Nvidia Control Panel (as a test) and just using the rFactor 2 profile that comes with Inspector, but that's up to you - I'm still not sure if it would help, but at least there would be no confusion over which rFactor 2 profile was taking affect.

Also if you are not familiar with Inspector I should say don't copy the 'Sparse Grid' settings from the rFactor2Inspector.jpg in my first post - this will cut your framerate a lot if you weren't using Sparse Grid previously (it's an image quality setting and not for improving performance). You probably already knew that, but I thought I'd point it out.

 

Unfortunately on Surround Sli this setting halves my fps on Silverstone

EDIT: I updated to the new Beta drivers (which then deleted my rf2 profile from NVCP) and using the settings above I can match what I had before, which was AA 4x in NVCP vs AA at Level 3 in-game, both giving me between 35-45fps around Silverstone with the Audi T5 mod, no AI, all settings maximum apart from Shadow (High), Shadow Blur (Optimum) & Environment Reflection (Low), with HDR OFF, V-SYNC OFF & FXAA OFF, playing in MultiView @ 5760x1200.

Does anyone know how to remove a profile from NVCP once added without uninstalling the drivers completely as the 'Remove' button remains greyed out?

 

Works great with 660 SLI,i doubled my FPS,amazing that ISI did not give us the solution ...

326.19 beta

Thanks a lot ForthRight for sharing.

 

some improvments also for my 460sli!