I only noticed this in P3Dv4 recently, but the issue became very apparent to me after i had tried a flight in the FSLabs earlier this year to find my framerate absolutely nosedived the seconds i went above 3 knots on the ground, so any normal taxiing speed. But, coming to a standstill, the framerates returned to normal (Standstill = 20-25 fps in VC, taxiing = 10-15 best case scenario)

What confused me was when the fps got better as soon as i was in the air, and then it was back to word not allowed the second i touched down 2 hours later.
This doesn't just happen on the FSLabs, it happens on all aircraft i have, even default.

I also noticed this problem in v5 when i tested it recently, but it baffles me that i've never encountered this issue before, at least, not to a significant extent.

Try the same but without any taxi, beacon or landing lights on. A combination of some aircraft and airports have a severe impact on the GPU pushing it to 100% usage which results in stutters.

Once you're airborne the lights are no longer illuminating the ground so performance increases to normal.

Another option is to turn off Dynamic Lighting which is quite poorly managed in v4 but is better in v5.

You can easily monitor GPU and CPU usage with Riva Tuner SS combined with MSI Afterburner. I keep RTSS display on all the time making it easy to monitor GPU and especially CPU1 usage.

4 hours ago, Ray Proudfoot said:

Try the same but without any taxi, beacon or landing lights on. A combination of some aircraft and airports have a severe impact on the GPU pushing it to 100% usage which results in stutters.

Once you're airborne the lights are no longer illuminating the ground so performance increases to normal.

Another option is to turn off Dynamic Lighting which is quite poorly managed in v4 but is better in v5.

You can easily monitor GPU and CPU usage with Riva Tuner SS combined with MSI Afterburner. I keep RTSS display on all the time making it easy to monitor GPU and especially CPU1 usage.

Thanks for the reply, i tried this and unfortunately encountered the same issue, DL on/off, lights off both times as well. My CPU usage has a noticeable spike to around 80% during taxi, however my GPU stays around 30-50% the whole way. This is at the default airport, but it happens at all airports anyways.

@BlueSwurl, I need to see your settings. Post some screenshots please. If you taxi with a default aircraft does it still spike?

9 minutes ago, Ray Proudfoot said:

@BlueSwurl, I need to see your settings. Post some screenshots please. If you taxi with a default aircraft does it still spike?

I do have the same issue with default aircraft, but numbers in that are basically always above 30 fps for me, typically 60 stable when stationary, then dips to around 35-40ish when moving.

Shadows at Ultra draw distance won't be helping you.
Low or medium is a better bet.

Turn all shadows off completely at night when using dynamic lighting.

Turn Dynamic Reflections to low or off.

Bring your Cloud Coverage Density slider to high or medium.

You're asking a lot from your PC with the settings as you have selected right now.

Does this problem also occur with other airplanes, or only with FSL A320?  Your settings seem fine to me.

@BlueSwurl, thanks for that. Autogen vegetation density should be lower.

What refresh rate is your monitor capable of? If 30Hz then select VSync = On with 30Hz selected in Nvidia Control Panel.

1 hour ago, F737NG said:

Shadows at Ultra draw distance won't be helping you.
Low or medium is a better bet.

Turn all shadows off completely at night when using dynamic lighting.

Turn Dynamic Reflections to low or off.

Bring your Cloud Coverage Density slider to high or medium.

You're asking a lot from your PC with the settings as you have selected right now.

These settings have worked well for me in this aircraft before, as well as with the current PMDG fleet, but i will try turning them down a bit.

35 minutes ago, Afterburner said:

Does this problem also occur with other airplanes, or only with FSL A320?  Your settings seem fine to me.

This problem occurs with all aircraft in the sim, it's strange because it's only started happening recently.

7 minutes ago, Ray Proudfoot said:

@BlueSwurl, thanks for that. Autogen vegetation density should be lower.

What refresh rate is your monitor capable of? If 30Hz then select VSync = On with 30Hz selected in Nvidia Control Panel.

I'll turn down my autogen, it is fairly high but i do like my trees 😉, and my monitor unfortunately is uncapable of 30hz. However, i don't think this is much of a problem with my settings or my hardware, but more of a problem with the sim itself. I say this because prior to this i was not experiencing the problem in any noticeable manner.

17 minutes ago, BlueSwurl said:

I'll turn down my autogen, it is fairly high but i do like my trees 😉, and my monitor unfortunately is uncapable of 30hz. However, i don't think this is much of a problem with my settings or my hardware, but more of a problem with the sim itself. I say this because prior to this i was not experiencing the problem in any noticeable manner.

Pity as 30Hz ensures the CPU and GPU are not overworked. Try monitoring CPU1 and GPU by installing RTSS from here and Afterburner from here. You set the preferences in Afterburner and RTSS displays them. As they always visible on screen you can easily see when either hits 100%. Just adjust your settings until 100% is rarely hit at your busiest airports.

No-one has mentioned Ai. Are you using any such as AIG?

2 minutes ago, Ray Proudfoot said:

Pity as 30Hz ensures the CPU and GPU are not overworked. Try monitoring CPU1 and GPU by installing RTSS from here and Afterburner from here. You set the preferences in Afterburner and RTSS displays them. As they always visible on screen you can easily see when either hits 100%. Just adjust your settings until 100% is rarely hit at your busiest airports.

No-one has mentioned Ai. Are you using any such as AIG?

I've used afterburner in the past so i actually have some numbers now, and typically with the FSLabs the usage on the ground when moving is typically 70-80%, and in the air it can be 80 to 100% depending on weather, however occasionally i get lower usage. GPU usage has never been a problem for me.

Other aircraft such as the PMDG don't have the same usage problem, but i do notice the drop with them as well, but the drop in FPS still gives me a manageable framerate (roughly 25).

I don't use AI traffic too, but i do notice it getting worse on VATSIM because of the models.

How recently did you notice the changes?  Was there a recent Windows 10 update?  If yes, you could try to uninstall these updates and see if that has an effect. There was a Windows update a few weeks ago that negatively impacted the FPS of some games.

13 minutes ago, Afterburner said:

How recently did you notice the changes?  Was there a recent Windows 10 update?  If yes, you could try to uninstall these updates and see if that has an effect. There was a Windows update a few weeks ago that negatively impacted the FPS of some games.

I first noticed this way back in February with a BA flight i did, i was getting a whopping 7 FPS down at Heathrow while i was taxiing. Of course, some of this in part was due to being at Heathrow on VATSIM, however at the departure airfield (Schoenfeld) i experienced a similar drop while taxiing.

I noticed the same problem while testing the 737 to see if it too was affected. 37 FPS stable, begin moving, hovers around and below 30. Same with basically every single aircraft in the sim.

I would deactivate all scenery add-ons and tools to revert to the default configuration to find out if one of them may be responsible for the phenomenon you described. While you do the test, monitor your CPU and GPU load to watch for any anomalies occur. Who knows, maybe there is some tool at work that interferes with the sim?

1 hour ago, Afterburner said:

I would deactivate all scenery add-ons and tools to revert to the default configuration to find out if one of them may be responsible for the phenomenon you described. While you do the test, monitor your CPU and GPU load to watch for any anomalies occur. Who knows, maybe there is some tool at work that interferes with the sim?

Just tried what you said, and the same issue was encountered. I even installed the previous version of FSUIPC to see if that made a difference, it did not. I'm honestly lost as to what the problem could be at this point.