ssair1

Best CPU for Prepar3dv4.2

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I'm currently running an Intel i7 7700K, o/c @ 4.9 GHz ( further hardware info in my signature), if I were to upgrade to i9-7980XE @ 2.6 GHz, would there be a fairly substantial improvement in performance, due to the "16" cores? I apologize for my lack of knowledge in this area, but I would like to get an idea of what more I can do: to improve performance. 

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1 hour ago, ssair1 said:

I'm currently running an Intel i7 7700K, o/c @ 4.9 GHz ( further hardware info in my signature), if I were to upgrade to i9-7980XE @ 2.6 GHz, would there be a fairly substantial improvement in performance, due to the "16" cores? I apologize for my lack of knowledge in this area, but I would like to get an idea of what more I can do: to improve performance. 

More then likely a decrease in performance due to lower clock speeds.  I can’t see your signature. What is your GPU?

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Posted (edited)

My prediction:  No.  :unsure:

You currently have the ideal CPU/GPU combination for P3D.  :cool:

Edited by Bert Pieke

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Would be a substantial performance downgrade due to lower clocks / lower OC potential. Fast, single-threaded performance is still king when it comes to the ESP platform. While P3D does use additional cores for terrain / autogen rendering, the actual performance benefits are hard to spot.

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I am quite happy with my overclocked 7820x (8 Core). You also have to consider RAM and GPU. My 1070GTX seems to be a little bit too weak for my CPU. You could go for a 7900x or maybe 7920x if they are o/c-able to at least 4.5-4.6 GHz., Though, I doubt that more than 12 cores allow enough o/c.

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Here I am using a 7940x ( 14 cores ) @ 4.8 - 4.6 - 3x 4.3 - 3x 4.2 - 3x 4.1 and 3x 4.0. No HT , no custom AM. So the main P3D thread is running at 4.8 Ghz.

 Before I had a 6 cores 5820x @ 4.3 Ghz.

If your main thread core now is running at 4.9 Ghz and , with the correct cooling solution , you would have the main thread on the 7980x running at 4.9 Ghz there would be a some improvement as the L3 cache is much biggger .

Beside that all other cores will be used for terrain / Windows / addon programs. You will have better terrain loading and less “stutters” from addon programs.

Rob A has a 7900x at 5 Ghz and Hans “Hasse” Westman has a 7980x at 5 Ghz. Better than that it won’t get when using a multimonitor or 4K Config with heavy aircraft and heavy scenery.

Less expensive and also very good is a 8700k Config ( 6 cores ).  5 Ghz is very normal with a good cooling solution.

regards, Gerard

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I also have a 7900X @5 Ghz without HT but still have small issiues with terrain loading, even with all my sceneries on a Samsung 960 EVO 1 TB M2 SSD.  I´m using a watercooled titan xp @ 2 Ghz and a 32 inch 4 K G-sync monitor. 

I can maintain 27 - 30 FPS (locked)  most of the time the only place where i´m not able to do this is EGLL 🙂 But that`s known there i have only 15 - 17 FPS. 

 

 

 

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2 hours ago, 331BK said:

I also have a 7900X @5 Ghz without HT but still have small issiues with terrain loading, even with all my sceneries on a Samsung 960 EVO 1 TB M2 SSD.

What cooler? I have all cores on my 7900X running at 4.8 GHz (no HT). I tried 5 GHz but it wasn't stable with P3D4. I did experiment with corres at different speeds, with core0 at 5 GHz, but couldn't really get any better performance.

2 hours ago, 331BK said:

I can maintain 27 - 30 FPS (locked)  most of the time the only place where i´m not able to do this is EGLL 🙂 But that`s known there i have only 15 - 17 FPS. 

Same here, except my EGLL (Aerosoft version at present, but UK2000 one is similar) does get to 19-21 fps after a little while.  FlyTampa EHAM is similar. This is with 3 scenery windows (no panels used) on 3 1080p Projectors (onto NatVis curved screen with 210 degree FOV). I am using SLI on 3 x 1080Ti GPUs, not overclocked.

I can get a little better performance with no AI Traffic -- I use a mixture of UTLive and MyTraffic, with the FSUIPC limiter set to 80 with a frame rate setting for that at 24.

I'd love to use 3x4k Projectors, but they aren't available (yet) with a sufficient short throw at an affordable price, and it think P3D would almost grind to a halt no matter what computer system is used.

Pete

 

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2 hours ago, 331BK said:

I also have a 7900X @5 Ghz without HT but still have small issiues with terrain loading, even with all my sceneries on a Samsung 960 EVO 1 TB M2 SSD.  I´m using a watercooled titan xp @ 2 Ghz and a 32 inch 4 K G-sync monitor. 

I can maintain 27 - 30 FPS (locked)  most of the time the only place where i´m not able to do this is EGLL 🙂 But that`s known there i have only 15 - 17 FPS. 

 

 

 

Just built my new LCS into my case. I used slightly higher OC settings : 4.8 - 4.7 - 12x 4.4.  Max 75 degrees on Core 0. Already I ordered 2 extra radiator fans for a push/pull Config which cools all cores by 2-3 degrees extra.

Here the leaktest :

 

 

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4 minutes ago, Pete Dowson said:

What cooler? I have all cores on my 7900X running at 4.8 GHz (no HT). I tried 5 GHz but it wasn't stable with P3D4. I did experiment with corres at different speeds, with core0 at 5 GHz, but couldn't really get any better performance.

Same here, except my EGLL (Aerosoft version at present, but UK2000 one is similar) does get to 19-21 fps after a little while.  FlyTampa EHAM is similar. This is with 3 scenery windows (no panels used) on 3 1080p Projectors (onto NatVis curved screen with 210 degree FOV). I am using SLI on 3 x 1080Ti GPUs, not overclocked.

I can get a little better performance with no AI Traffic -- I use a mixture of UTLive and MyTraffic, with the FSUIPC limiter set to 80 with a frame rate setting for that at 24.

I'd love to use 3x4k Projectors, but they aren't available (yet) with a sufficient short throw at an affordable price, and it think P3D would almost grind to a halt no matter what computer system is used.

Pete

 

Pete , only the main P3D core has to run as fast as possible . All terrain cores can run 4.3 - 4.5 as they won’t reach even 20% load . Windows will choose whatever it wants. To be sure I have core 1 running at 100 MHz slower than core 0 so Windows can start on a fast core too.

Regarding EGLL : I have my framerate locked at 22 for airports like EGLL and FT EHAM. Autogen trees : normal and autogen buildings : dense. No AI car traffic.

When doing sightseeing above True Earth Netherlands I set the framerate to 20 , no shadows , clouds distance : 50 , no AI Traffic .LOD radius minimum . 

What also helps is using Nico Kaans Live Traffic instead of MT / UT.  Everything is calculated outside of P3D and it gives way better fps.

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Posted (edited)

Hey guys, 

i use custom watercooling loop with 1x 480 1x 380 and a aquacomputer kuplex kyros HF with .925 silver 

I think to purchase a new motherboard a evga x299 dark because it has perfect vrm cooling and 2x 8 pin connector for cpu. maybee i can then hold the 5 ghz with less v core. currently 1.29 V on a flight from FlyTampa Corfu to ORBX englad with Aerosoft EGLL the max CPU temprature is about 67-68 Degree Celsius (delided cpu). 

At flytampa EHAM or Aerosoft EDDF Professionall (with ORBX North and South Germany) i can get between 25 - 30 FPS only EGLL is heavy.  But i think the FSL A320 has also a big part on that. 

It`s interessting to see that with locked FPS the terrain loading seems to work better but with unlocked the flight is smoother but the terrain loading slower even with my monitor set to 30 hz.

 

I also allready thought about having the first core at 5 Ghz and the others at 4.8 or something like that. But i thougt steve w somewhere said that it`s not a good idea. 

Edited by 331BK

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9 hours ago, mpw8679 said:

More then likely a decrease in performance due to lower clock speeds.  I can’t see your signature. What is your GPU?

 My GPU is the Aurous GeForce GTX 1080TI Xtreme Edition 11GB. I think you have hidden your display signatures preferences. 

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Now knowing better jumping from   I 7 7700K @ 4.9 to I 7 8700 K @ 4.9 I find unnecessary spending $ 2,000 when my FPS gain was not more than 3. The only difference I can see is due to a higher core number my scenery textures are loading faster, unfortunately its not so much. The other issue I can see is that P3d core usage is not quite well balanced across the cores. I would wait for a new update version on P3D and make a decision based on what they fixed regarding performance, otherwise IMHO you burn money.

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3 hours ago, GSalden said:

Pete , only the main P3D core has to run as fast as possible . All terrain cores can run 4.3 - 4.5 as they won’t reach even 20% load .

Actually I regularly get over 50% load on at least three others.

As I said, i did try different core speeds with only the mainone at 5 GHz, but i think it must have upset some other timing someplace (memory maybe?). It nearly worked, but P3D would crash occasionally. Going back to 4.8 fixed that. And really the difference in performance was negligible -- not really worth further hassle.

Pete

 

 

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24 minutes ago, Pete Dowson said:

Actually I regularly get over 50% load on at least three others.

As I said, i did try different core speeds with only the mainone at 5 GHz, but i think it must have upset some other timing someplace (memory maybe?). It nearly worked, but P3D would crash occasionally. Going back to 4.8 fixed that. And really the difference in performance was negligible -- not really worth further hassle.

Pete

 

 

The difference between 4.8 and 5.0 is 4% in cpu speed difference which might be just 2% more fps performance....

I never see more than 15-20% load on the terrain cores. If I apply an AM , then those cores go to 50-100% many times...

Did you try without HT and without AM ?

regards, Gerard

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Sure is sounding like a topic for the Hardware forum to me... :cool:

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How do you determine which cores Prepar3dv4 is using? Does anyone know what is the maximum number of cores, according to LM, that P3d utilizes? Does threaded optimization make a difference? Ok... I guess I need to find some good resource materials on this subject? Any recommendations? 

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Posted (edited)
1 hour ago, ssair1 said:

How do you determine which cores Prepar3dv4 is using? Does anyone know what is the maximum number of cores, according to LM, that P3d utilizes? Does threaded optimization make a difference? Ok... I guess I need to find some good resource materials on this subject? Any recommendations? 

I am not sure there is a maximum.. it is more a case of the benefit you get from farming out work to ever more cores..

Just like 9 women cannot create a baby in one month, there is a practical tradeoff in terms of coordinating the effort.

From what I have read on these forums, a 4-6 core CPU is plenty for scenery loading which is really all the additional cores do. The raw speed of the main P3D core is ultimately what determines actual rendering performance (alongside the other critical components like motherboard, memory and GPU, all of which are part of the effort).

Edited by Bert Pieke

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Posted (edited)

I had always the opinion that it is better to have all cores at the same speed. I seems that I am wrong. But how much difference between main core (core 0) and other cores is "allowed"?

Edited by Nemo

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4 hours ago, ssair1 said:

How do you determine which cores Prepar3dv4 is using?

With only P3D running, open up the Windows Task Manager and check the "Performance" tab. Then check with P3D closed. The difference must be all P3D (the rest Windows and other background services).

There's an "always on top" option in "Options" if you want to check with P3D in its "pseudo" full screen mode.

Pete

 

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3 hours ago, Bert Pieke said:

From what I have read on these forums, a 4-6 core CPU is plenty for scenery loading which is really all the additional cores do.

Yes. Whilst I let P3D use any or all cores as it wishes, I set the core affinity for other processes (and for FSUIPC's own internal threads, such as for Lua plug-ins and WideServer) to cores other than those which Task Manager shows P3D actually using most. Thus, for me at least, whilst not all the cores are fully loaded, at least I'm making good use of them all! 😉

Pete

 

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Quote from Beau Hollis , LM P3D Architect :

”The default behavior is to use all cores. The only purpose of applying an affinity mask would be to disable one or more cores. We don't recommend this, but we recognize that it may be beneficial in some cases. For example, there could be an add-on that communicates with another application. There could also be other unrelated windows applications running, that users don't want to close when they run Prepar3D. Higher fidelity training devices often rely on additional applications to perform simulation work. In that case, the system might be configured to allocate specific cores to specific applications. This can be done via OS settings, but the AM setting in the cfg makes it a bit easier.

The other use case that is often mentioned is to disable the hyper-threaded core that shares a physical processor with the primary thread. Sometimes doing a full workload on the HT core can slow down the primary. This is really chip and workload specific. We updated our job scheduler in v2 or v3 such that it typically uses core 1 without overloading it. In our tests, even with HT on, using all cores was typically better than masking off core 1 after the scheduling changes were made. Since then, we have not recommended custom AM settings. 

One last thing I should note is that add-on dlls are considered to be part of the Prepar3D process. The AM settings will be applied to those dlls as well. Add-on developers may be creating their own threads and assigning heavy work loads to them.”

 

 

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52 minutes ago, GSalden said:

One last thing I should note is that add-on dlls are considered to be part of the Prepar3D process. The AM settings will be applied to those dlls as well. Add-on developers may be creating their own threads and assigning heavy work loads to them.”

Yes, this is why FSUIPC's individually-specifiable AMs must be a subset of those set for P3D (which is best left default therefore), and why I check which cores P3D is using mostly so I can specifically assign other processes and threads to less-used ones.

This check seems only to be needed once as P3D seems to choose (or be allocated) the same cores each time. I should probably check this again on every new P3D release, though.

Pete

 

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I'm running the same CPU clocked at 4.9 in software with smart fan it did get to 5ghz but I limited t to 4.9, on a 28inch 4k panel, I noticed when I ran it on RivaTurner  for tweaking it ran mostly at 4.6-4.7 and only hit max when you do a view change at high detail area then drops back,

I have my sim locked at 30 fps and stays there again only on very high detail airports it will drop but it will stay above 20 fps with PMDG aircraft.

    

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Hi all,

I was wondering if someone could offer some advice please.

I have a new system similar to those mentioned here, Asus X299 Deluxe Prime motherboard, i9 7900x CPU running at 4.6Ghz, 32gb Ram and 3 x 1080ti cards with SLI bridge installed.

I am very unfamiliar with setting up SLI.

I also have 3 projectors and use Immersive Display Pro for warping. I was running a 6700K CPU with 2 980ti's and it ran fairly well. It had 1 projector on one GPU and 2 projectors on the other in non SLI because the MB did not support it.

For the life of me I cannot get decent frame rates with the new system. I have tried one GPU for each projector. (Woeful!) All projectors on 1 GPU in SLI (better but still not great) and the best FPS I get is the 3 projectors on one GPU not running SLI. (ie 2 GPU's sitting there doing nothing)

In the first 2 scenarios, as soon as I create a new window (for testing purposes) and undock it, the FPS plummets. There is only a small FPS hit in the 3rd configuration.

I have not changed anything in the Nvidia Control Panel except to enable SLI so I don't think that is the problem unless there is another setting I don't know about.

I have read many forum posts and tried a multitude of suggestions but nothing seems to work for me.

Any suggestions would be appreciated and thank you for your time.

Best regards

Rob Broadbent

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