You can have as much clock speed as you want, but if you can't get it to the GPU to render, it doesn't matter.

 

 

No P3D process is upgrading the graphics engine and eventually moving to a higher version of DirectX, right now they are fixing DX10 preview and making it full DX10 compatible.

 

P3D is DX11.

You can have as much clock speed as you want, but if you can't get it to the GPU to render, it doesn't matter.

I'm not sure what this even means. But, in FSX, the GPU doesn't matter much at all. You need one, of course, but it doesn't matter which one, in terms of FPS.

The GPU isn't used much because it has to sit there and wait for the CPU to send it things to draw.

 

Source: Microsoft (third paragraph)

 

Use a low resource aircraft like the Ultralight, and your GPU usage and FPS will be high.

 

Use a medium resource aircraft like the F-18 (Acceleration pack) and your GPU usage and FPS will be medium.

 

Use a high resource aircraft like the PMDG 777 and your GPU usage and FPS will be the lowest of the three.

 

The Ultralight issues 12 draw calls per second.

 

The F-18 issues roughly 500 draw calls per second.

 

The PMDG 777 issues 1400ish draw calls per second while in the VC.

I'm not sure what this even means. But, in FSX, the GPU doesn't matter much at all. You need one, of course, but it doesn't matter which one, in terms of FPS.

Not entirely true. The GPU handles resolution, AA and AF. A stronger GPU will reduce performance loss caused by those functions. Allowing you to use higher resolution AA/AF settings, without FPS loss.

 

 

Source: Microsoft (third paragraph)

 

Thank you for that link.

The GPU isn't used much because it has to sit there and wait for the CPU to send it things to draw.

 

Source: Microsoft (third paragraph)

 

Use a low resource aircraft like the Ultralight, and your GPU usage and FPS will be high.

 

Use a medium resource aircraft like the F-18 (Acceleration pack) and your GPU usage and FPS will be medium.

 

Use a high resource aircraft like the PMDG 777 and your GPU usage and FPS will be the lowest of the three.

 

The Ultralight issues 12 draw calls per second.

 

The F-18 issues roughly 500 draw calls per second.

 

The PMDG 777 issues 1400ish draw calls per second while in the VC.

 

Sorry, but that makes no sense (to me)..

 

If the Ultralight issues only 12 draw calls per second, what exactly is keeping the GPU so busy?

 

Also, that was written in 2007.. we now have systems those guys could only dream of.

 

When I upgraded my GPU from a GTX460 to a 770, I could suddenly fly into very heavy scenery, like Vancouver+ V3, without fps loss (fps locked at 30).  Before, it would drop to 20 in the detailed areas and become stuttery..

 

Also 2xSGSS was handled without any performance impact..  somehow, this GPU upgrade had a positive impact on overall smoothness.

If the Ultralight issues only 12 draw calls per second, what exactly is keeping the GPU so busy?

 

A "lightweight" airplane gets through it's CPU processing faster, so it can kick frames over to the GPU for processing faster. This, in turn, gives the GPU more to do and will use more GPU cycles as it tries to keep up with the frames being sent to it for the given resolution, AF, and AA settings.

 

A "moderate" airplane is a little slower through its CPU phases, thus giving fewer frames to the GPU to process, thus easing the work the GPU has to do.

 

A "heavy" airplane is the slowest out of the gates of the CPU, providing even fewer frames to the GPU for rendering. In an interesting twist, that means the GPU may actually be doing less work.

 

-Greg

A "lightweight" airplane gets through it's CPU processing faster, so it can kick frames over to the GPU for processing faster. This, in turn, gives the GPU more to do and will use more GPU cycles as it tries to keep up with the frames being sent to it for the given resolution, AF, and AA settings.

 

A "moderate" airplane is a little slower through its CPU phases, thus giving fewer frames to the GPU to process, thus easing the work the GPU has to do.

 

A "heavy" airplane is the slowest out of the gates of the CPU, providing even fewer frames to the GPU for rendering. In an interesting twist, that means the GPU may actually be doing less work.

 

-Greg

 

Sounds kind of neat, except for the math is shaky...

 

If the heavy airplane issues 100 times more draw calls, that should keep the GPU plenty busy, unless the Ultralight runs at framerates more than a 100 times faster, which it does not..

More draw calls, less FPS.

 

Not just in FSX, but any other program. Just like that link I posted was saying.

OK, I stand corrected... if you run at unlimited framerate settings!

 

I just ran a little test

 

FPS unlimited:

Hawker       60 fps,  GPU load 36%

Ultralight    130 fps, GPU load 43%

 

FPS locked at 30:

Hawker       30 fps,  GPU load 19%

Ultralight    30 fps,  GPU load 12%

Your tests seem to validate this theory.

 

When left unlimited and untouched, the ultralight produces many more frames. This puts a stress on the GPU to perform the post-processing things like anti-aliasing that many more times per second.

 

If you artificially limit the framerates, both airplanes are playing on a level playing field in that respect. Now, the cost of the draw calls shows its face in the equation, and the heavier airplane has the higher GPU load.

I ran my tests with VSync off and frames at unlimited.

 

 

 

 

 

 

 

More draw calls, less FPS.

 

Not just in FSX, but any other program. Just like that link I posted was saying.

 

What will amaze people is that some objects in the autogen libraries contain 3-4 drawcalls each and there are over 500 objects without even going into things like trees, aircraft, airports, VC's etc!

Because we keep trying to stuff a seven course meal into a stomach that can only handle one and it gives our PC's indigestion which makes it poop all over our frame rates?

Because that donkey can only carry so much weight on the cart before this happens: