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marty2756

Understanding X-Plane performance

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Hi

Last week I bought a Zodak Gforce 780 TI AMP edition, 3GB mem , (780 ti oveclocked). I had a 580 gtx previously. I knew this should bring a good fps improvement for x-plane, at least in sceneries that CPU is not bottleneck-guilty.
I measure this by reading the in-screen "CPU" usage reported by x-plane. Ben said in his devlog that we could think as CPU being a constraint with readings above 0.95 or so.
Yesterday I started the sim at LEMD (Madrid-Barajas) Default aerosoft airport, Simheaven City photoscenery, OSM Europe,
starting at gate or a runway several times, I was getting 14-17 fps. :huh:
OK, main rendering options used:
- World distance: high
- Number of Objects: too many
- Roads: (At max)
- Shadows: Global medium
- Cars: Syberian
- HDR on
- Textures: very hgigh (compressed)

What I've checked:

- CPU x-plane reading, never above than 0.80
- Checked every CPU core with Windows task manager, the busiest core in terms of CPU usage, was never getting higher than 70-75% usage. (We know x-plane uses one core for most of the rendering work)
- GPU performance with Afterburner, going from 30% to 40% usage.
- Size of textures loaded within x-plane (in rendering options screen):  1.2 GB  (I particulary checked this, because yes, if usage is near VRAM capacity  frame rate drops a lot)
- Plugins: just using skymax proo . (tried disabling it for a while, and just a 3 fps gain, so Skymax is not the problem)
- Not paging or disk-intensive usage.

Still... 14-17 fps. (tried with jar-a320 and other aircraft too)
Hardware: Sandy Bridge i5 overclocked at 4.2 Ghz, 8GB RAM + Zodac Gforce 780 TI Amp edition, 3 GB.

Any Ideas ? I don't understand , except BUSes stuff what can be the constraint in these situations.
 

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Turn the evil HDR off!!!  (would be the first thing I would do)

 

Also OSM cities can eat frames for lunch.

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OSM is quite heavy on the frames. I can run objects at mega tons with my GTX 670 2GB and an i5 3570 at 4.2 GHz. In demanding addons like the FF 757 or the LES Saab 340A my frame rate can drop down to around 20 but 18-19 is the lowest I see, that is with HDR on. Make sure that the road traffic is set to the lowest setting, it's really demanding on the CPU. Also, turning the shadows down from "global high" to "3D on aircraft" resulted in an immense performance boost.

HDR is just too important and beautiful to turn it off...

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Too low cpu usage may be your reason IMO.

Try to make cpu usage at about 0.92 but sure not higher than 0.95.

Put shadows on "Melt your gpu" and a maybe more objects.

 

Powerful system shows it's glory when you are demanding it to it,right now you are. Not.

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Turning off HDR doesn't seem to improve FPS in my case,, something expected as I don't see GPU Usage with more than 40% .....

@mtaxp: what I can't understand is... what is the constraint right now , that "gives me" just 14-17fps..... CPU ? as per my checkings above NO........GPU neither (less busy than CPU, as expected)..  VRAM not... Disk I/O not... so ?

motherboard bus speed ? or x-plane perhaps just no 'coordinating' work to exploit full hardware capabilities ?don't think so but sill ... don't understand why.

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Try this, load the sim, and then go to the weather and download real weather. Now check your Fps again. The cpu should be up near 0.98 and using it's full capacity. Works for me everytime and maintains at least 30fps.

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When demanding more from the CPU in terms of graphics it'll demand more from GPU as the CPU sends a "draw list" to the GPU.

Try to raise the shadows and the AA in HDR mode (Shadows are CPU intensive and AA is GPU),in your case IMO your CPU should be at 0.992~,but not 0.995< .

 

As you can see lowering your rendering settings doesn't help at all,instead of demanding more from your system you're demanding less.

 

Here are some shots that can explain better:

 

13620568695_840b253270_o.png

 

13620576455_87e23dc218_o.png

 

 

Watch the FPS and the CPU in the first picture,comparing to the FPS and the CPU to the second one.

 

Nevertheless,I clearly need more GPU power,which makes sense,I have an OLD GTX 460 1GB.

BTW my settings are higher than your's,every thing is at MAX excpet from clouds (40%) and HDR is on 4XSSAA (in 2XSSA mode I'm at about 15-20 FPS in the same situation),and texture resolution is Very High (no compress,but I'M using more VRAM than my GPU limit though)

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If shadows are cpu intensive, why is the setting called 'melt your GPU'? Shouldn't it be 'melt your cpu'?

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If shadows are cpu intensive, why is the setting called 'melt your GPU'? Shouldn't it be 'melt your cpu'?

It melts both! ;-)

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Hi

 

Last week I bought a Zodak Gforce 780 TI AMP edition, 3GB mem , (780 ti oveclocked). I had a 580 gtx previously. I knew this should bring a good fps improvement for x-plane, at least in sceneries that CPU is not bottleneck-guilty.

I measure this by reading the in-screen "CPU" usage reported by x-plane. Ben said in his devlog that we could think as CPU being a constraint with readings above 0.95 or so.

Yesterday I started the sim at LEMD (Madrid-Barajas) Default aerosoft airport, Simheaven City photoscenery, OSM Europe,

starting at gate or a runway several times, I was getting 14-17 fps. :huh:

OK, main rendering options used:

- World distance: high

- Number of Objects: too many

- Roads: (At max)

- Shadows: Global medium

- Cars: Syberian

- HDR on

- Textures: very hgigh (compressed)

 

What I've checked:

 

- CPU x-plane reading, never above than 0.80

- Checked every CPU core with Windows task manager, the busiest core in terms of CPU usage, was never getting higher than 70-75% usage. (We know x-plane uses one core for most of the rendering work)

- GPU performance with Afterburner, going from 30% to 40% usage.

- Size of textures loaded within x-plane (in rendering options screen):  1.2 GB  (I particulary checked this, because yes, if usage is near VRAM capacity  frame rate drops a lot)

- Plugins: just using skymax proo . (tried disabling it for a while, and just a 3 fps gain, so Skymax is not the problem)

- Not paging or disk-intensive usage.

 

Still... 14-17 fps. (tried with jar-a320 and other aircraft too)

Hardware: Sandy Bridge i5 overclocked at 4.2 Ghz, 8GB RAM + Zodac Gforce 780 TI Amp edition, 3 GB.

 

Any Ideas ? I don't understand , except BUSes stuff what can be the constraint in these situations.

 

Did you update Nvidia driver with new card?

 

Olga Vankranendonk

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Tried re-downloading real-weather but CPU usage and FPS still remails the same.

 

I raised the shadow setting to "Melt you GPU", FPS still remans the same.

 

I attach both screenshots of rendering options, and the jar a320 parked at gate in LEMD, there you can

see x-plane CPU reading (0.8) task manager CPU per Core usage, and GPU Usage.

 

Still, Its ok the that raising shadows to Melt your GPU does not kill my frame rate more , because of the good GPU. (we take advantage of that)Thats ok. What still cant figure out is what component is constraining FPS to 17 ~.

 

(Sorry for screenshots as links, I couldn't manage to attach them as images)

https://www.flickr.com/photos/122430773@N04/13652478543/

https://www.flickr.com/photos/122430773@N04/13652431053/

 

@LTPuce: Yes, downloaded latest drivers for 700 series. :/

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Are you running X-Plane in full screen or windows mode?

I had a similar problem where my fps were limited and CPU usage was between 60-70%

Switching back to full screen made my CPU usage go back over 95% and of course gain a lot of fps.

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Few things:

* I suggest that you don't compress your textures,you have ALOT of room for VRAM,And even EXTREME with no compress will still be OK, and you gain more quality.

* Antistropic just put it to 16X...you will gain more quality and with no FPS hit of course.

* Lock your frame rate,this'll preven tearing.

 

the 3 above just were graphic suggestions that will not cost you anything,only WIN situation ;)

 

Try raising your world distance to VERY HIGH (more cpu usage)

Airport detail to the mximum

Objects to Maximum

Cars to maximum

 

And report back 

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Absolutely true! Textures should be compressed, roads should be set to tons or mega tons and shadows, although they look very appealing, especially during dusk and dawn, should be set to "3D on aircraft". I have set World distance to medium, turning it down from high had a noticeable effect on the FPS. Clouds can be very demanding too, I have set my cloud detail to 20%.

How all of this looks can be seen on my video, here in the screenshot and video section "X-Plane 10 beautiful approach into LSGG". With my setting, I get very stable 30 fps with a minimum of around 22-24 over dense city sceneries, and this is while I am streaming on twitch with 720p. Reasonable settings are very important!

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Well, played cranking up world distance to very high, airport detail to max, antristropic to 16, cars, and objects.

All combinatios resulted in the same (17) or less FPS, altought not too much, all to max got about 13 or 14fps, something expected somehow.

 

Anyway, I could lower everything down,... till I get MORE than those 17 ugly fps.... but the the question still is,

why ... if I don't have a CPU constraint neither a GPU contraint I ONLY get those fps.

 

Quoting from Ben Dev Blog:

"Here’s the key point: your framerate is determined by the processor that is not idle.  If your GPU is idle and your CPU is not, you are “CPU bound”; if your CPU is idle and your GPU is not, you are GPU bound."

 

So in this situation... my GPU is Idle by far,,, and my CPU is idle too , altough not so much as GPU.....

so.... WHAT is "determining" my 17 fps limit ?

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I didn't tell you to crank everything while i'm expecting that you'l get solid 30,wanted to see how cpu affected.

Is the cpu usage remains the same even after that?

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So in this situation... my GPU is Idle by far,,, and my CPU is idle too , altough not so much as GPU.....

 

so.... WHAT is "determining" my 17 fps limit ?

 

Do you happen to have any AI Aircraft, especially default ones loading into the sim? They tank my FPS even the ones that are suppose to be optimized. Also are you seeing these low fps everywhere or in a specific location, maybe a bad scenery? Lastly from what I have read on Ben's blog I would never consider running texture compression especially with 3-4gb of vram but I suppose that's a personal preference.

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Lastly from what I have read on Ben's blog I would never consider running texture compression especially with 3-4gb of vram.

 

Well with everything maxed out, there is no choice, otherwise it is too much. Way above 4GB. Trust me, I know, I have 4GB....and I've tried! 

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Well with everything maxed out, there is no choice, otherwise it is too much. Way above 4GB. Trust me, I know, I have 4GB....and I've tried!

I find it hard to believe you could even have playable framerates with everything "Maxed Out" so what's the point?

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I find it hard to believe you could even have playable framerates with everything "Maxed Out" so what's the point?

 

I can maintain 30FPS, not 'everything' is maxed, but I put my GPU to use, so things that are GPU bound I max, I have very high settings. Lowest I go is around 22 in somewhere like London. And I know if I don;t compress textures, I go way over. I am at 3800MB on GPU-Z in an OSM city area, with compressed. Imagine uncompressed?!

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I can maintain 30FPS, not 'everything' is maxed, but I put my GPU to use, so things that are GPU bound I max, I have very high settings. Lowest I go is around 22 in somewhere like London. And I know if I don;t compress textures, I go way over. I am at 3800MB on GPU-Z in an OSM city area, with compressed. Imagine uncompressed?!
Cool, glad it works for you.  Now back on topic...So the OP got a new card  went from a 580gtx to a 780ti and doesn't seem happy with the results? Hmmm, sometimes the simplest solutions often get overlooked; did you update your drivers? Any Nvidia or Nvidia Inspector setting that might be causing the poor performance?  Once those are checked why not go to a default location and "set all rendering options for maximum speed" then build yourself up increasing the rendering options as you go? Might help in troubleshooting the issue...Good luck

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@mtaxp:. cranking up those options,  gradually increases CPU usage reading within X-Plane, yes,.... goes UP till 0.945 ~.... (with everything at max), except Cars, that I have it at Kansas Residential.

I understand your point trying to maximize usage of CPU right ?

But do you get my point ? What I try to achive is..... STAY with my original rendering settings... and understand... WHY is that I can't get MORE fps (than 17),,, if there is ROOM left ,, (idle processors) for CPU as for GPU.

Don't know if I you get what I mean.

@Blaze: yes I have 6 AI aircraft, but those are Mortens AI,, very low on FPS... by the way.. I tried setting them to 0 AI.. and If I get 1 more FPS ... is too much.. anyway .. if this would be the cause... my point still remains... why ... if there is processing power left on both cpu and gpu sides... can't get more fps. "Bus" is the only thing that comes to my mind.

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i know this might sound weird but is there any way you can partition you hd and install a fresh windows and xplane. something sounds very wrong with how much FPS your getting with ur HD

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@marty2756

Maybe some conflicts with the older ones,which common when changing the GPU...Try to unistall anything that's realted to NVIDIA and then install a FRESH new driver.

Moreover,as @saed45 said try to install a fresh copy of your operating system,and then install new fresh drivers

 

Usually those situations are the result of CPU bound,I mean...you are CPU bound (GPU is almost idle,but CPU does some work though) but your CPU has much more room to work... 

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