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Some folks may already know this, but add or change this setting in your Prepar3D.cfg

 

[Display]

TEXTURE_BANDWIDTH_MULT=160

 

This works very well for my Titan Black, went from 30 fps to 42 fps with no stutters.  Default value is 30.

 

I must admit, it was the FSX:SE thread and I think Vic that mentioned this ... so give them (or others) full props.

 

Cheers, Rob.

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Will the increase in FPS equate to smoothness? Its not always the case as I already have high FPS with P3D but it stuttery.

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Will try it tomorrow and see how my 2 Titans in SLI behave.

 

Rob , a little of topic question : since I have set my Titans in SLI my system sometimes need 3 times to boot up.

Each time before switching to the desktop the pc restarts itself 1 or 2 times extra.

Dropbrox shows 2 extra windows instead of just one.

 

When turning off SLI all issues are gone.

 

However when running the system is completely stable and P3D is performing great....

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Some folks may already know this, but add or change this setting in your Prepar3D.cfg

 

[Display]

TEXTURE_BANDWIDTH_MULT=160

 

This works very well for my Titan Black, went from 30 fps to 42 fps with no stutters.  Default value is 30.

 

I must admit, it was the FSX:SE thread and I think Vic that mentioned this ... so give them (or others) full props.

 

Cheers, Rob.

 

Rob, I did a search here just yesterday on the TBM settings and almost all replies posted stated that it does nothing. My 1st thought was why did the devs leave it in. 

I will give it a shot.

 

Bob

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I normally discard such claim of "40% FPS increase in P3D" instantly, but I'm amazed that this comes from Rob. Sure I'll give it a try tonight. It'll be unbelievable if this TBM=160 indeed works to jump my fps from 30 to 42!

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I had no significant change between the default of 30 and the 160 entry.  I even monitored GPU usage... and that was literally the same.  Using a "dated" GTX 570 here.

 

I didn't do any thorough testing... just default mooney on the ramp at a default airport, identical weather, no AI.

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Just tried it with my 4gig 760 and no change. I had a little hope but now I need to go have a piece of Christmas fudge.

 

Bob 

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Just tried it, and I think there might be some benefit to be had. I don't think its another case of me seeing what I want to see - there does appear to be a genuine rise in FPS.

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Thanks for posting this up Rob. I had lost hope with getting P3D 2.4 running on my rig but over the past 3 days I completely re-installed and stepped through each tweak one at a time and I'm happy to say that this tweak has pushed my FPS up to the mid to high 60's from the mid 40's to mid 50's. This is of course, without any weather so if I can maintain a steady mid to high 30's I'll be very excited.

 

Thanks again and props to Vic and the folks tweaking/playing around with FSX-SE!!

 

Mike

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Very interesting idea.  I actually tried this in FSX to see if anything would happen and I think I got a good bump and no small pauses either.   I guess I will have to fly with it for a while to see if it is real.

 

Default Scenario

TMB = 80

FSDT Vancouver, ORBX Global, Vector, ASN, PMDG737

Frames in the VC - 22 - 25

 

Test

TMB = 160

FSDT Vancouver, ORBX Global, Vector, ASN, PMDG737

Frames in the VC - 22 - 30 (mostly 28 to 30 but it did dip down a few times when looking around the vc).

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Very interesting idea.  I actually tried this in FSX to see if anything would happen and I think I got a good bump and no small pauses either.   I guess I will have to fly with it for a while to see if it is real.

 

Default Scenario

TMB = 80

FSDT Vancouver, ORBX Global, Vector, ASN, PMDG737

Frames in the VC - 22 - 25

 

Test

TMB = 160

FSDT Vancouver, ORBX Global, Vector, ASN, PMDG737

Frames in the VC - 22 - 30 (mostly 28 to 30 but it did dip down a few times when looking around the vc).

 

No effect in FSX on my system ,same as above but with PNW at gate 54 i am at 30-33fps (Locked 40)

 

Michael Moe

 

(remember to switch off shadows with the NGX in FSX ,it gives you a 5-10% boost as well) (DX10 cant handle NGX VC shadows anyway)

 

Will try P3D

 

Update: No effect on my system in P3D

 

i7-4770K@4,7GHZ

GTX780SC 3GB

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Interesting, is this the mysterious FSX steam edition boost trick emulated on P3D?

 

Going to have to give that a go tomorrow.

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I asked about this after the release of 2.0 about the value of 30 and why so low of a default setting. Didn't get a definite answer except that the setting may be depreciated for P3Dv2 and left in there for compatibility. Back then I tried 120 and saw zero impact on my system so reverted it back to the default of 30.

 

At any rate the way I see it if your GPU is already maxed out you would probably see no benefit from this setting. If your GPU is being artificially held back due to this setting then you may get a benefit from it. As with any other tweak it will affect each persons individual system differently based on their hardware thats why we are seeing different results. 

 

Edit : My initial thought was that they kept it at a low number because of adding tesselation to the GPU so as to leave a bit of headroom for that to work...

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Tried the config change in P3dv2.3 and there was no change in fps in three separate test scenarios. No one's set up is exactly the same, so what works for one simmer may not for another. The change, however, did not decrease fps so I'll leave in and see how it goes in other flights.

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I tried every conceivable TBM combo with P3D quite some time ago.

 

Absolutely no difference. I too have a Titan Black.

 

YMMV

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I changed mine in FSX years ago on advice of NickN and have added it to all my systems since. A lot depends on how well your system is balanced, IIRC in my conversations with Nick, it is more like a "final" kick once everything else is in order.

 

But, as noted, just like every other tweak - YMMV.

 

BTW, a trick that SE uses to affect FPS in FSX:SE- reduce your default zoom - you'll get an increase.  :lol:

 

Vic

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A lot depends on how well your system is balanced

 

Yep. Don't get your hopes up on this. As I wrote in the FSX-SE compatibility threads, for most setups, this tweak won't improve performance. Rob has two Titan Black GPUs and that may explain his experience.  Anyone with either a GTX 980, GTX 970, Titan or GTX 780 ti should test this in P3d and report back.

 

 

TEXTURE_BANDWIDTH_MULT=160

 

You might want to go higher, like to 400 or 800, since the Titan Black has a bandwidth of 336 GB/s, as does the GTX 780 ti. Probably any card either near or above 200 GB/s bandwidth might see an improvement as long as the setup is not CPU-limited.

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Keep in mind that when it comes to GPU bandwidth, there are two types. The first is how fast the system communicates with the GPU. This is determined by the PCIe version (mostly 2.0 and 3.0 these days) and the slot type (8x, 16x, etc.). This communication consists of sending DirectX commands to the GPU and is generally not the limiting factor unless one has a fast GPU and a slow CPU. The second type is how fast the GPU itself communicates with its VRAM. Those GPU bandwidth numbers in my previous post are for that type of bandwidth. This bandwidth affects how fast information is sent by the GPU to the screen.

 

Although no one (except possibly someone from ACES) quite understands what this setting does, most people online have assumed that it somehow impacts the second type of bandwidth. I could be way off on this, as I'm only regurgitating what I have read over the years.

 

Also, probably people should also point out their CPU and clock speed when reporting results.

 

" -- UPDATE SP1 -- (from Phil Taylor's blog) 
The mysterious sounding TEXTURE_BANDWITH_MULT is our first target. This is a setting in the [DISPLAY] section of the file, formatted like this: 
[DISPLAY] TEXTURE_BANDWIDTH_MULT=n 
Where n can range from 10 to some reasonable value that is related to your frame rate limit. 
From Rafael Cintron, part of the FS Graphics and Terrain team, comes this description: 
“The TEXTURE_BANDWIDTH_MULT option in the Graphics section is the target frame rate use for calculating texture bandwidth. The higher you set this value the more textures we will allocate and copy per frame to the graphics card. The lower you set this value, the less we will allocate and copy up to a minimum limit. As an example, the default rate in the “high” perf bucket setting is 40. The lowest perf bucket setting is 10. 
Higher settings on this flag can cause stutters on frames where the terrain system has finished compositing lots of textures. Lower settings can reduce stutters on busy frames and spread out the load across multiple frames“ 
So thinking this thru, if the value you set is 40, and your frame rate limit is 30, then we will send 40/30 or 4/3 as much textures per frame. 
Moving this value to 400, like I have seen some users post in the forums, is probably *not* what you want to do since that increases the texture load on the graphics card by 10x, eg 400/40 = 10x. And after talking about this to Raf, setting it to 0 is ignored and can be validated by setting it to 10 which should give no different results. "

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I've had mine set at that for some time now.  Works like a charm and combined with the FFT being at 0.01 I get great performance with no blurred textures on my setup.  If you are seeing little or no change I think its because your video card is already doing all it can with what it's got.

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