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Rob Ainscough

P3D V3.2 Performance SLI vs non-SLI and other stuff...

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I did some "relative" performance testing today to get an idea of how settings impact my P3D V3.2 experience.  Here are the results of that testing:

 

dc37e1bf4109bf52fb4386bb33c0a38f.jpg

 

The baseline graphics settings I used as a starting point are HERE.  The above table indicates variances from the Baseline.  There are NO tweaks, the Prepar3d.cfg is "as is".  The 5960X has HT OFF so 8C/8T.

 

Test flight scenario files HERE for anyone that wants to compare with their setup.

 

I recorded the test flight and placed on YouTube in case others want to replicate see HERE.

 

The native FRAPS timeframe output files are HERE if you want go over them in detail - suggest using FRAFS viewer.

 

Points of interest for me from this data is:

1.  Item 3 and 6, SLI vs. non-SLI for 2X SGSS ... SLI performs about 23% better.

2.  Item 7 and 11, SLI vs. non-SLI for 4X SGSS ... SLI performs about  46% better.

3.  Item 13 and 14, 8X SGSS vs 8X MSAA ... MSAA performs about 42% better.

4.  Item 18 and 19, 2160p vs. 1080p ... 1080p performs about 24% better.

5.  Item 1 and 2, 4.3 GHz vs. 4.6 GHz ... 4.6Ghz performs about 34% better in the 0.1% time (less fluctuation) but equal in Avg and 1% time.

6.  Dynamic Reflections OFF vs. Medium seem to have no significant FPS impact (with SLI)

7.  Terrain Shadows 0 or 80,000m appear to have no significant FPS impact (with SLI)

 

This is for my specific setup, I do/did have 176 Add-Ons installed when doing this test, obviously NOT all active at the same time, but just an FYI.

 

Cheers, Rob.

 

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Thanks for sharing. Now we have at least some numbers to compare different settings and setups. Remarkable is item 18 and 19, the impact of resolution. Cheers, Chris

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Excellent work. Thank you for this. SLI comes out as a "winner" in P3D.

 

Were these tests done at 30Hz or 60Hz? Not that I think it would make any difference in the results!!

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Well all this time I thought there was no extra benefit from SLI but it looks like there is.

 

I'll be puchasing another 980ti I guess.

 

Thanks Rob.

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Remarkable is item 18 and 19, the impact of resolution.

 

Yes, keep in mind that was 8X SGSS AA.

 

 

 


Were these tests done at 30Hz or 60Hz?

 

Test were done with monitor at 30Hz, but to be noted in RED text, P3D was set to Unlimited and Vsync was OFF ... so basically whatever my PC could do with those graphics settings and add-ons.

 

 

 


I'll be puchasing another 980ti I guess.

 

Yes, but be aware, if you run at 60Hz there still isn't enough in SLI at 4K res with my add-ons and graphics settings to hit 60 FPS.  So  you'll need to either dial back add-ons, resolution, and/or graphics settings to hit 60Hz.  But it does certainly seem SLI + SGSS AA do work better.

 

Cheers, Rob.

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I run at 30hz 4k single monitor so a second gpu should help just a little more. My sim runs a steady 30 so just looking for a little more headroom in those tough situations.

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Rob, It's very interesting.

But I still do not understand why with SLI my two GTX 980 are smooth only with unlimited frame.
In v2.5 everything worked perfectly also with FPS locked at 30 (Nvidia driver?).

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Wow...

Looking at your test results, I might benefit from a second Titan X for SLI, if NVSurround and 3 screens will be supported....

 

Have you done a test : SLI vs Non SLI ---> 4x MSAA / 8x MSAA ( no SGSS ) ?

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Rob great chart, thanks. Have you tried Bandicam for frame rate overlay? I used to use fraps but because I now have 4k I find fraps to be too much overhead (frames went from 120 to 14 when recording 4k but Bandicam went from 120 to 30).

 

Not sure if the overlay is much concern with either but it seems smoother with Bandicam.

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Hi Rob, I am using sli and notice you refer to SGSS & MS..... are these types only available using Nvidia inspector and do you think NI is a must for using? If so, do you have a list of recommended settings for 2 GTX980 ? Currently running MSAA at 4 and vsync, with FXAA & SSAA both off......

 

Thank you

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But I still do not understand why with SLI my two GTX 980 are smooth only with unlimited frame.

 

Unlimited with Vsync is my prefered choice for 30Hz monitor with or without SLI, but if you run a 60Hz monitor then you'll need to sustain 60 FPS at a minimum IF you use Vsync.  My rule of thumb for setting Unlimited vs. limited is HERE.

 

 

 

Have you done a test : SLI vs Non SLI ---> 4x MSAA / 8x MSAA ( no SGSS ) ?

 

Test 14 and 9 is pretty close to what you're asking as it seems Dynamic Reflections (Off, Low, or Medium) don't seem to have much impact on performance (see test 11 and 12 with SLI).

 

I have no information on SLI with multi-monitor, sorry.  I have a 3 monitor test PC setup, but it's not SLI (just a single 970 GTX) and I have not used NV Surround (in P3D I just stretch the window across my 3 displays and then Alt+Enter which is not the same as NV surround).

 

 

 

Have you tried Bandicam for frame rate overlay?

 

I have all kinds of software options for frame overlay including GPU usage, temps, timeframe, etc. etc. (EVGA Precision X is my preferred choice for OSD).  I'm not actually trying to "record" a flight with FRAPS, I use ShadowPlay for that since it's hardware accelerated and has minimal impact to performance.  I only use FRAPS for timeframe analysis since it does a very good job of it and has a FRAFs viewer which makes it easy to look at the data.

 

 

 

Hi Rob, I am using sli and notice you refer to SGSS & MS..... are these types only available using Nvidia inspector and do you think NI is a must for using?

 

MS is the standard Multi-Sample that P3D uses, no need to have nVidia Inspector for this.  SGSS does require nVidia Inspector.  Here is how you set SGSS (note this is with the older NI v1.9.7.3, current version is v1.9.7.5 but use the same settings):

 

e2ee4ed35568a2cbe91f94540e9a7712.jpg

 

The "High Quality" setting is optional (I've not seen much of a difference).  I would NOT recommend using FXAA with anything other than MSAA.  Some people have good success with DSR, I have not so I don't use it.  I don't see much of a visual difference between MSAA and SSAA, I only see a visual difference when using SGSS.

 

SGSS AA is the best AA I've used, but it does come with a performance hit AND power hit ... in fact, with 4K res and 8X SGSS it actually triggered my APC power backup/line-conditioner to kick in and I was very close to exceeding the power limits of 110-120v 15 Amp power circuit running to my simPit room.  Time to rethink home power options -- or maybe our home solar setup just couldn't handle it :)

 

Cheers, Rob.

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Rob--thanks for this. Which nVidia driver were you using for these tests?

Cheers

Edit: never mind, I see it there in the NVI window header (358.50).

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Bob,

 

No, that screen shot is old (just for reference) ... drivers used for testing 364.51.

 

Cheers, Rob.

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Did you face any OOM during a flight with those resolutions?

I'm not with 5960X but with 6700k and 1x Titan X, not SLI

 

I tried similar maxed out settings, didn't have problems with some airports, but at Heathrow after ~30min flying over the area.

(ORBX England, OpenLC Europe and default Heathrow) I had OOM issue.

 

I'm using P3D V3.2 Academic.

 

Max Vram was ~2.5Gb and ~2Gb of Ram

 

Any tips?

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Hey Fabio,

 

It's been a long long time since I've had any OOMs (going back to P3D V2.x).  Only tips I can provide:

 

1.  Stay with 2048 textures or lower (1024)

2.  If you have OpenLC EU than use Orbx FTX Global and not England region

3.  HT off saves me about 400MB VAS

4.  If you have high levels of AI traffic use AI traffic limiter (available here on AVSIM)

5.  Use default clouds or REX soft clouds (no 4096 textured clouds)

6.  Enable only the 3rd party airport you plan to fly to/from

 

Cheers, Rob.

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I'd like to ask rather a amateur question about SLI in v3.2. If I run my sim on a single 1440p monitor in 2560x1440 resolution with 1024 (sometimes 2048) textures, will second 980Ti really help me with FPS increase in dense clouds (meaning 4xSGSAA will be ON) or not? I see that you guys are running multi-monitor set-ups, a solution I'd like to stay away from.

 

Thanks

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I run single monitor on my main FS PC, my triple monitor setup is on my FS Test PC.

 

Yes a 2nd 980Ti in SLI should help in dense clouds with 4X SGSS AA, HOWEVER, you need to keep in mind that if you currently drop to 19 FPS (as example) in dense clouds, that 2nd 980Ti would at best case get you up to about 27 FPS and worse case 24 FPS ... for some that might be enough for other's it's still not good enough.  So take whatever your current lowest FPS is in dense clouds and add 25-45% for worse case and best case.

 

I'd recommend using 512 textures (default clouds or REX soft clouds) for cloud textures ... I think some folks have dropped to 256 textures with very good results.  Depends how important it is to you to have very detailed cloud textures.  But if you run 4X SGSS then I'd recommend 512 or 256 cloud textures regardless of SLI or non-SLI.

 

Cheers, Rob.

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Hey Fabio,

 

It's been a long long time since I've had any OOMs (going back to P3D V2.x).  Only tips I can provide:

 

1.  Stay with 2048 textures or lower (1024)

2.  If you have OpenLC EU than use Orbx FTX Global and not England region

3.  HT off saves me about 400MB VAS

4.  If you have high levels of AI traffic use AI traffic limiter (available here on AVSIM)

5.  Use default clouds or REX soft clouds (no 4096 textured clouds)

6.  Enable only the 3rd party airport you plan to fly to/from

 

Cheers, Rob.

 

1) Lowered to 2048

2) Will test that, I had Europe region activated

3) I need to go to BIOS settings to change it right? It will be a pain in the a** to change everytime I want to fly, but will give it a try

4) I don't use AI Traffic, only IVAO / VATSIM traffics

5) I use REX Texture and Soft Clouds (they are at 4096 now, will change to 2048)

6) That shouldn't be an issue with P3D V3 right? Since it only loads the active area you're flying

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3.  HT OFF works well for VAS on my 5960X, don't know if it works well on your CPU ... but P3D doesn't seem to like 8C/16T.

 

5.  Strongly suggest you drop cloud textures to 512

 

6.  Depends on how many 3rd party airports you have active in the area ... for heathrow close proximity area, I think I have several airports that could be active (Aerosoft, UK2000, Orbx) at the same time since is a very dense area for population and airports

 

Cheers, Rob.

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My Fs runs smoother with 32 bit clouds than DXT5 clouds...

Don't know why but it does...

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I'd recommend using 512 textures (default clouds or REX soft clouds) for cloud textures ... I think some folks have dropped to 256 textures with very good results.

 

Is that what is listed as CLOUD_SHADOW_TEXTURE_SIZE in the .cfg file?  The "shadow" part was throwing me off.

 

Thanks,

Jeff

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Does MFAA work with P3D?

 

Edit :I know it doesnt work with SLI but just curious

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Does MFAA work with P3D?

 

It did work for me with 2X SGSS in SLI ... but difference was very minor at 4K res, I didn't do any testing with MFAA ... why would it not work with SLI?

 

 

 


Is that what is listed as CLOUD_SHADOW_TEXTURE_SIZE in the .cfg file?  The "shadow" part was throwing me off.

 

Not related, that's the shadow map size ... it'll govern how sharp cloud shadows look on the terrain.

 

 

 


My Fs runs smoother with 32 bit clouds

 

That's my experience also, but this might be GPU dependent.

 

Cheers, Rob.

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It did work for me with 2X SGSS in SLI ... but difference was very minor at 4K res, I didn't do any testing with MFAA ... why would it not work with SLI?

 

Well it was reported as being broken since the 900 series cards were released when used with SLI but I currently don't run SLI so have no way to check. Maybe they got around to fixing it finally. Same with DSR when used with custom refresh rates.

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