How I got SLI mode working... Yes, this time it works!

[toby23]

EDIT - Quirk! has found a working fix for SLI - See HERE for more info

 

I have almost got SLI mode working properly at native resolution.

 

The culprit was a combination of the in-game SHADOWS setting and RES. OF COCKPIT DISPLAYS.

By reducing SHADOWS to Medium and setting RES. OF COCKPIT DISPLAYS to 512 every frame all the problems have gone.

No more flickering, no more jagged lines (edit - I just flew a campaign mission and the jagged TGP lines came back) and no more huge performance hit in WHOT/BHOT mode.

 

The only problem left, and it is hardly noticeable, is that there is a very slight stutter in WHOT/ BHOT mode when you look out the right side of the cockpit and only when there are a lot of trees in view. Perhaps an option for tree density might help in a future patch?

 

Even though the cards aren't being 100% utilised, I see a major improvement in smoothness with SLI active at 2560x1600 resolution.

Max memory usage with 4xAA in-game and 2x AA Transparency Supersampling forced (smoother than in-game TSSAA) was 1492mb and Max GPU usage 72% using 2x GTX580 cards.

Anisotropic filtering 16x is automatically controlled by the Sim, I found out, so I removed that from the Nvidia Control Panel.

 

My in-game settings are below as are my Nvidia Control Panel settings.

 

Happy hunting.

 

Toby

Edited July 26, 2011 by toby23

[KKR75]

Toby, thanks for your update. I'll be trying that setup and let you know my findings. I've been struggling with flickering, jagged lines, stuttering when trackIR panning, frame rate redux with bhot/whot, etc... I'm running 3-way SLI with gtx 480s and 12GB RAM. My max res is 1920x1080 (running a single 32" LCD TV display).

[CADelta]

If this do in fact solve the slow SLI performance and the other SLI issues, then you are THE MAN kind Sir. :thumbup:

 

Will most certainly test this out as soon as I got some time on my hands again.

 

 

/Krycek

[BTTW-DratsaB]

All investigations and reports are useful so no offence is meant by this...But for me the thing that needs to be fixed with SLI is that we can't run a non Every frame setting without getting flicker on the TGP with SLI enabled.

Having to run an Every Frame setting to fix the SLI problems counteracts any advantage that SLI is giving in the first place. If that makes sense.

 

If you could have SLI enabled and run a non Every frame option you would get a large boost from SLI.

 

You are running 2x Supersampling and 4x Anti-aliasing ( and a huge res) though, which is extremely hard on your GPU, so SLI is probably helping with that.

 

But, running an EveryFrame option has always "fixed" SLI problems since DCS A10's release.

Edited July 25, 2011 by BTTW-DratsaB

[toby23]

After a fresh install of 1.1.0.9, my old SLI settings stopped working and I got a huge performance hit using WHOT/ BHOT TGP. After playing with the settings, this is what works for me for now.

I totally agree with you that we need a setting for SLI that works which isn't EVERY FRAME.

[Gonzo01]

Toby I tried your settings on my rig and unfortunatly they did not help regarding the huge performance hit or the cloud flicker. The only thing that helps is reducing the MFCD to 512K ever frame from 1024K every frame, but that just gives me 2 or 3 more FPS. The lower res looks fuzzy and out of focus, which is why I don't use it. The other setting make no difference. I have vsync on so when I use the TGP in WHOT/BHOT I still get a 35 frame hit from 60 down 25 FPS and in CCD mode it a 30 FPS hit. Either way it is a big performance hit.

Edited July 25, 2011 by Gonzo01

[toby23]

Gonzo, try restoring the Nvidia Control Panel settings.

If you have been messing with Nvidia Inspector, also reset settings for Black Shark to default.

This only worked for me after I had really reset the settings to default.

Good luck

[Gonzo01]

Gonzo, try restoring the Nvidia Control Panel settings.

If you have been messing with Nvidia Inspector, also reset settings for Black Shark to default.

This only worked for me after I had really reset the settings to default.

Good luck

 

I will give it try. Thanks for all the effort by the way. I know everyone appreciates you trying to make it work. :)

[Gonzo01]

Toby I think your onto something. I reset the video setting to their defaults like you said and then made my adjustments accordingly. Keep in mind that I still have a little cloud flicker, but it's a lot less than what I had before and when I get close to a cloud it stops flickering all together. Also, I am still running the MFCD's in 1024K every frame, because it looks much sharper, but the key here is you are right about your setting being an improvement. I am no longer dropping into the 20 FPS range. It seems to be holding above 35 FPS with TGP on and in the WHOT mode and the MAVs online as well. Nice work:))))

[Kuky]

The thing with SLI/CF and non every frame setting getting flickering I believe, is because one card/gpu is set to render main game screen and second card/gpu does the TGP, if this is true for every 2 frames the game does there is only 1 frame for the cockpit displays so the lack of one frame causes flickering (screen is filled black, or maybe white, I don't know as I haven't seen this with my own eyes).

 

I personally find every frame setting to work much nicer, thought at some FPS hit, but if you have SLI/CF it shouldn't be too bad (as long as 2 card give higher FPS then 1 card)