Limited v Unlimited

[Steve Waite]

With FSX you can set the number of frames per second (fps) for drawing the display.
You can set “Unlimited Mode”.

With Unlimited Mode, the time between each frame can vary dramatically and can spoil the view with rain and snow.

You can set “Limited Mode”.

With Limited Mode it is only any use if the fps always stays constant. If the fps drops during Limited Mode, that is a kind of Unlimited Mode.

When you switch to Limited Mode you notice what appears to be a severe drop in available fps, this is because there is at least 1 look ahead frame being drawn. Look ahead frames, mean that some work can be done on the next frame, if in Limited mode there is still time for the game loop to process it.
In terms of visual appeal, you can get away with 13fps. But it’s better to have more than that; 15fps is just about OK. Better to have 17fps, it is more liquid; and 19fps properly fluid.

Remember if you have 19fps and go to 24fps you are demanding 25% more power!

If you have addons, like moving maps, and network gizmos they may run better with FSX in Limited Mode, but only if the frames are set low enough so that they don’t change. This requires a powerful PC.

With FSX you need smoothness of flow, not big fps numbers.

[jscharpf]

Steve this has always puzzled me. I've seen many others recommend limit the FPS to 20 or something like this.
However, I have found with FSX that if I set it to unlimited, I get really smooth frame rates.. well actually sure they're jumping around but I don't notice it.. My game seems to run better. Maybe it's my perception.

If I limit the FR, my game seems to run a little jerky.

Once and a while I get a hesitation when it appears to be loading textures but I don't care about that.

Just wondering if I'm the only person on the planet that gets a better sim set to unlimited lol.

Jeff

[Steve Waite]

There is always a big debate as to which is best.

I found limited is, on my system, with my setup, but only if it is truly limited. Setting 20fps and seeng 16-19.8 half the time is like unlimited, in a way. You need to see a consistent 20 if set to that. If you don't you will be suffering lower frame rates for nothing. True unlimited would be better.

Unlimited runs free and gives huge framerates, but inconsistent looking rain and snow.

You can get glitches with either approach, depending on the scenery. Remember with IF, the weather takes twice as long to set up because it constantly changes. You can see the delay when you start a flight (updates are much quicker as you travel) But it only does this infrequently.

As far as tweaking goes, I increased LOD_RADIUS to 9 and the whole system ran more smoothly, the swathes of autogen so far away that it was tiny, and did not interrupt flow. But I could struggle to get 15fps limited. Although later when I turned into a very dense patch of autogen, FSX crashed. So I should try 8 next, see if it's more reliable.

It all depends on scenery, autogen, the PC hardware/drivers and lots of other things. To try and find out how your setup can be improved is a good thing.
Steve