Nividia SLI compatibility?

[Quirkitized]

That is old information. SLI has bee working in windowed mode for quite some time now.

 

I don't have SLI but my friend does and he does not get SLI peformance in starcraft 2 or warcraft in windowed mode, or f1 2010. Switch to full-screen and he gets the sli boost in fps. He has two 285's so not sure if that has something to do with it.

[Callsign.Vega]

I've found that Force Alternate Frame Rendering 2 gives the best results with SLI

 

Confirmed. You need to force only AFR2 to get SLI to work properly with DCS titles. You get a nice performance boost with AFR2 single monitor! AFR1 and SFR both tank performance. There are no DCS SLI profiles so you need to make them yourselves or change the default SLI profile.

 

I use a handy tool called nVidiaInspector: http://majorgeeks.com/NVIDIA_Inspector_d6630.html

 

The only downside to AFR2 is you cannot use D3DOverrider to force triple buffering with VSync on. You might have to live with some screen tearing. Triple buffering with SLI only works in SFR.

 

I will test nVidia surround SLI performance tomorrow and report back.

[TwoLate]

Confirmed. You need to force only AFR2 to get SLI to work properly with DCS titles. You get a nice performance boost with AFR2 single monitor! AFR1 and SFR both tank performance. There are no DCS SLI profiles so you need to make them yourselves or change the default SLI profile.

 

I use a handy tool called nVidiaInspector: http://majorgeeks.com/NVIDIA_Inspector_d6630.html

 

The only downside to AFR2 is you cannot use D3DOverrider to force triple buffering with VSync on. You might have to live with some screen tearing. Triple buffering with SLI only works in SFR.

 

I will test nVidia surround SLI performance tomorrow and report back.

 

 

Thanks for the info. Yes I have Nvidia Inspector. Like it better than Nhancer. I will try this when I get a chance. AFR2 is the key.

[Slayer]

Confirmed. You need to force only AFR2 to get SLI to work properly with DCS titles. You get a nice performance boost with AFR2 single monitor! AFR1 and SFR both tank performance. There are no DCS SLI profiles so you need to make them yourselves or change the default SLI profile.

 

I use a handy tool called nVidiaInspector: http://majorgeeks.com/NVIDIA_Inspector_d6630.html

 

The only downside to AFR2 is you cannot use D3DOverrider to force triple buffering with VSync on. You might have to live with some screen tearing. Triple buffering with SLI only works in SFR.

 

I will test nVidia surround SLI performance tomorrow and report back.

 

Not quite right. There is a profile for DCS:BS 1.0 in the driver. When ED patched the game to 1.02 they broke the compatibility fixes in the driver because they renamed the .exe to simulator.exe

 

There are several other problems with the way the Nvidia driver applies profiles

 

1) It only checks that an .exe file is running without any hash checks to confirm that it is the proper game/executable - The problem with this is that now FC2 and DCS:BS have the same exact name simulator.exe There are some settings that work in BS but not FC2. I may be wrong here but doesn't LOFC also have simulator.exe ( I think that this was the original reason DCS:BS was given a different .exe name in the beginning????)

 

The graphics engine is most definately not exactly the same since the original DX8 lockon.

 

2) Now throw into the mix DCS:A10-C .....also named simulator.exe but with a newer graphics engine that may or may not require the old fixes(who knows) and adds several new graphics enhancements.

 

No wonder people can't get consistancy. It's using driver level fixes for 3 or 4 different versions of the same engine.

 

I've posted this on the ED forums and Nvidia forums before with no reply on either side....

Edited November 30, 2010 by Slayer

[copen]

I run A-10C with 3x 30" at 4800x2560, SLI is needed for surround. With this high of a resolution both 480's go to max utilization and I am GPU limited, not CPU.

 

So you're running each of the displays in portrait mode? I didn't realize 30" displays rotated on their stands. Or are you using a tri-display mount? What's your CPU/RAM config?

[Callsign.Vega]

Not quite right. There is a profile for DCS:BS 1.0 in the driver. When ED patched the game to 1.02 they broke the compatibility fixes in the driver because they renamed the .exe to simulator.exe

 

There are several other problems with the way the Nvidia driver applies profiles

 

1) It only checks that an .exe file is running without any hash checks to confirm that it is the proper game/executable - The problem with this is that now FC2 and DCS:BS have the same exact name simulator.exe There are some settings that work in BS but not FC2. I may be wrong here but doesn't LOFC also have simulator.exe ( I think that this was the original reason DCS:BS was given a different .exe name in the beginning????)

 

The graphics engine is most definately not exactly the same since the original DX8 lockon.

 

2) Now throw into the mix DCS:A10-C .....also named simulator.exe but with a newer graphics engine that may or may not require the old fixes(who knows) and adds several new graphics enhancements.

 

No wonder people can't get consistancy. It's using driver level fixes for 3 or 4 different versions of the same engine.

 

I've posted this on the ED forums and Nvidia forums before with no reply on either side....

 

If there once was a SLI profile for DCS:BS, it's not there anymore. I've checked nVidia's latest drivers and it is not there. There are no driver level fixes that need to be done. All you need is a correctly setup SLI profile utilizing AFR2 which you can simply make yourself. SLI is working great in both DCS titles and maxing out both my 480's.

 

So you're running each of the displays in portrait mode? I didn't realize 30" displays rotated on their stands. Or are you using a tri-display mount? What's your CPU/RAM config?

 

Yes, portrait mode. With the plastic bezels removed and with bezel correction to compensate for the remainder, I run 5090x2560 resolution. I have 3x HP ZR30w's clamped together which have a stand tall enough to rotate portrait. As a matter of fact I even have about three centimeters clearance from the desk.

 

My machine is a i7 @ 4.55Ghz, 6GB DDR3, SSD and 2x 480's (soon 580's).

[TwoLate]

Vega I tried in nvidia panel and Nvidia Inspector and forced AFR2 and cannot get the sli to work. Can you export your profile in Inspector and send it to me? Thanks.

[copen]

Yes, portrait mode. With the plastic bezels removed and with bezel correction to compensate for the remainder, I run 5090x2560 resolution. I have 3x HP ZR30w's clamped together which have a stand tall enough to rotate portrait. As a matter of fact I even have about three centimeters clearance from the desk.

 

My machine is a i7 @ 4.55Ghz, 6GB DDR3, SSD and 2x 480's (soon 580's).

 

That sounds like an ideal system. Can you tell me where you purchased/configured such a system? 4.55Ghz will require some serious cooling.

 

I don't suppose you have a picture of your monitor setup to share? I'd like to see how the clamp/mount works. Thanks.

[airdog]

Vega's setup here http://forums.eagle.ru/showthread.php?t=59536

[Callsign.Vega]

Vega I tried in nvidia panel and Nvidia Inspector and forced AFR2 and cannot get the sli to work. Can you export your profile in Inspector and send it to me? Thanks.

 

I don't have any special profile to get SLI working properly. I just select SLI rendering mode at the very bottom of the SLI category: SLI_RENDERING_MODE_FORCE_AFR2 in nVidiaInspector, hit apply and it just works.

 

What kind of hardware setup do you have?

[TwoLate]

I don't have any special profile to get SLI working properly. I just select SLI rendering mode at the very bottom of the SLI category: SLI_RENDERING_MODE_FORCE_AFR2 in nVidiaInspector, hit apply and it just works.

 

What kind of hardware setup do you have?

 

 

Yea I tried that.

 

EVGA 780I ftw sli motherboard

core duo E8500

2 260gtx scc evga

4 Gigs of 1066 memory.

Two SDD drives.

[Callsign.Vega]

Yea I tried that.

 

EVGA 780I ftw sli motherboard

core duo E8500

2 260gtx scc evga

4 Gigs of 1066 memory.

Two SDD drives.

 

What drivers are you using? What are your A-10C settings? What FPS do you get with one card, and what FPS do you get with both in AFR2?

[TwoLate]

Driver -260.99

A-10c settings do not matter It is not highest I am after. I have a 28 inch monitor so I run 1920x 1200. What is important is I do my ramp test with the same settings with or without sli to get a good benchmark. In cockpit looking straight forward I get 45 fps one card or in sli I get 46. In sli with the sli bar visible, My GPU usage is around 51% for both cards. Cpu is around 65% to 75% for both cores.

Edited December 1, 2010 by TwoLate

[Callsign.Vega]

Driver -260.99

A-10c settings do not matter It is not highest I am after. I have a 28 inch monitor so I run 1920x 1200. What is important is I do my ramp test with the same settings with or without sli to get a good benchmark. In cockpit looking straight forward I get 45 fps one card or in sli I get 46. In sli with the sli bar visible, My GPU usage is around 51% for both cards. Cpu is around 65% to 75% for both cores.

 

Your SLI is working fine. If there was a SLI problem your FPS would tank. I bet your single GPU goes almost to max usage and drops down to ~50% each with two cards like you said for virtually the same FPS. Your just CPU limited is all.

 

I take it your using Win 7? You will not show 100% CPU usage in Win 7 as will dynamically load the main sim thread between the two cores and a little bit extra one core for the sound thread.

 

I also get CPU limited when view distance is set too great and theres tons of buildinds/trees. GPU utilization drops and FPS drops hard even with a i7 @ 4.55Ghz. It's the sim software crapping out and not taking advantage of available hardware.

Edited December 1, 2010 by Callsign.Vega

[TwoLate]

My friend has a Intel Core i7 980x Extreme Edition 3.33GHz and he gets no increase of frame rates. On my rig With sli or without sli the cpu throttles back any way. On his extreme cpu he has the turbo boost where it increases during load up to 3.8 and he sees no increase in sli. For some strange reason a select few have a magic bullet. Sli is working but no increase in fps. If this sim was coded for sli like BlackShark it would be no problem to get more FPS. Why can I get FPS increase in Black Shark and not DCS A10?

Edited December 1, 2010 by TwoLate

[Callsign.Vega]

My friend has a Intel Core i7 980x Extreme Edition 3.33GHz and he gets no increase of frame rates. On my rig With sli or without sli the cpu throttles back any way. On his extreme cpu he has the turbo boost where it increases during load up to 3.8 and he sees no increase in sli. For some strange reason a select few have a magic bullet. Sli is working but no increase in fps. If this sim was coded for sli like BlackShark it would be no problem to get more FPS. Why can I get FPS increase in Black Shark and not DCS A10?

 

I have found A-10C in it's current beta form to be much more CPU limited over BS. Even on my 4.55Ghz system all I have to do is turn down the graphics to unload the graphics card(s) yet I don't get much of a FPS boost as I just run into the CPU limit wall.

 

Heres another test for you. If you say your GPU's are only being used 50% load, turn on like 4-8x or even 16x AA. That will stress them a lot more and your FPS should stay the same until your GPU's max out. If your GPU's scale up usage with the high AA then that confirms SLI is working properly and your CPU limited.

[BTTW-DratsaB]

SLI Works well, but...

 

hmm there is indeed a lot of misinformation in this thread.

 

I use GTX295 and run SLI. Within Nvidia driver 260.89 (and previous ones) there is a profile called "Digital Combat simulator: Black Shark". This also works with DCSA10, as the .exe's share the same name. You don't need to make a profile.

 

I was having some problems with DCS:A10 when using the TGP or Maverick camera. The Image on the MFCD starts to go corrupt and "flickery" showing the terrain wireframe through the ground texture. (I would take a screen shop but it wont pick it up).

 

I turned off SLI and the problem ceased. But... I lost massive amounts of FPS compared to running in SLI mode, particularly when the TV cameras where on and in Cockpit view in general.

 

So SLI is making a big difference to this Sim. But we need to have the targeting cameras fixed so they don't cause this corruption. Question is...who is supposed to fix this?

 

With these multiGPU issues you get the feeling that the devs (not just ED btw!) are like, "that's not our problem, Nvidia have to fix it in their drivers because xyz". And nvidia are like, "that's not our problem, the Game devs implemented something in a way that isn't compatible so they must fix it" etc. And poor Mr End User is like, "uhh we have been waiting for 2 years since release, can one of you get this fixed please?" :D

 

I just hope some one can take note of this problem and get it fixed before the sim goes gold.

[Slayer]

I get the flickering also BUT if you set the MFCDs to display every frame it pretty much goes away.

 

Got my other 480 GTX back from Gigabyte...There is a big improvement in smoothness of gameplay. Single card tends to slow down whenever you have the MFCD's in view but SLI with AFR2 really smooths things out.

Edited December 4, 2010 by Slayer

[Wazoo]

So... I decided to try some tests as well.

 

I'm using Beta 3 and loading the Weapons Training mission which starts you on the runway facing into the sun.

 

I tried EVERYTHING.... from no SLI, to using SLI, to no AA to 16QAA, to with and without HDR, and 1024x768 as well as my native single monitor res of 1600x1200 and no matter what, I get 16-19 fps when I'm dropped in the sim.

 

Interestingly, the SLI bar shrinks significantly when looking at the sun, but grows substantially if I turn my head away.

 

So it seems that SLI is working, kinda.

 

As this is an easy thing to replicate, I'm curious what others find.

 

Wazoo