GTN 750 when undocked ~50% frame rate drop - solved

[joepoway 241]

Fellow Flight Simmers

 

Recently I developed a problem with my GTN 750 application across all my aircraft.

 

I run a second monitor so I can open my GTN 750, undock it, and move it to that monitor so it doesn't block any of my VC and it's much easy to observe and modify. I find this very useful and have coupled it with custom view window mods in my config file so I can toggle it on and off instead of default maps.

 

Recently when I would undock (without even moving it) my GTN 750 my frames would drop from a steady 30 fps to 15 fps and return to 30 fps when I would "re-dock" it and this new behavior was across all my aircraft I had assigned the GTN 750.

 

After many failed attempts to find the cause I finally came across an old forum post and tried it and sure enough it fixed the issue of frame rate drop and allowed me to continue to use my GTN 750 as I had for the past year or more.

 

The culprit was Nvidia Inspector. I had recently tested running their external frame rate limiter at 30 fps (v1) in their P3D profile to see if would improve my performance (I had read running external limiter with internal P3D unlimited can improve performance on some systems) and found it to be virtually no difference so I set it back to off but forgot to hit Apply hence leaving it still set at 30 fps (v1). I went back in today set it to off and hit Apply this time and the frame rate issue disappeared. I toggled the frame rate limiter back on in Nvidia and it comes right back.

 

So I don't claim to understand why the Nvidia Inspector external frame rate limiter caused this behavior when I undocked a second view window like my GTN 750 but it did every time.

 

As a reference I run P3D unlimited with vsync and triple buffering on, while using a 4k Samsung TV which runs naturally at 30Hz giving me excelent performance.

 

Hope someone might find this useful!

 

Joe

[gboz 157]

I see this is still happening with p3dv4.2, at least when I undock the ATC menu with frame limiter in NI.

gb.

[joepoway 241]

On 2/13/2018 at 1:03 PM, gboz said:

I see this is still happening with p3dv4.2, at least when I undock the ATC menu with frame limiter in NI.

gb.

Seems to not be a P3D issue perhaps and have something to do with undocked separate windows. In general I make sure to run my GTN 750 in only one incidence even if I have the ability to put two systems in my cockpit that some aircraft enable because of the overhead. 

If you monitor the CPU usage you will see up to 10% used by the Garmin all by itself. I also use Process Lasso to keep it off core zero but it seems to like two cores so I Run it on cores 1 and 2 on my 4 core processor.

Thanks for sharing

Joe

[gboz 157]

1 hour ago, joepoway said:

Thanks for sharing

Joe

Hi Joe.

Just to clarify I am not using the GTN 750 at all at the moment. Just un-docking the ATC window drops the frame rate. So I guess it will happen with any un-docked window when using an external frame rate limiter. I read that using the GeForce Experience game overlay may also cause this problem.

gb.