Well, if you’re willing to be flexible in your definition of “highest” and “best”, sure. You can do all sorts of things to improve your frame rate and/or memory consumption.
If you’re asking the question, “My frame rate is X and I want to make it better, what can I do?” we can help you answer that question.
But if you’re asking the question, “Why is my frame rate X and then suddenly jumps to Y after I minimize and restore the window,” well, I have to shrug and say I don’t know, but it’s probably something funny your driver is doing.
I can make some guesses. When you minimize the window, all of your assets get removed from graphics memory. When you restore the window, they all get put back in. It’s possible that your texture memory happened to be arranged in a suboptimal order, so that the graphics card had to jump back and forth across texture memory in order to render your scene, blowing any internal caches. And maybe when it reloaded, it happened to put them back into a more optimal order, so that the caches were better utilized.
But all that happens at a very low level, under the hood from Panda (or from any other middleware graphics engine). We can’t control it. I can’t even guarantee that it will always happen that way–maybe next week, when you minimize the window and restore it, it will suddenly come back with a much worse frame rate.
Also, as to your memory utilization, what you’re seeing is the resident memory, which is different from total memory. When you minimize the application, if you are running on a low-memory machine, then most of the application will be swapped out of main memory to make room for other applications. When you restore the window, then those parts of the application that are currently active will be swapped back in. As you use more of the application’s memory image, more of it will come back in, but the immediate appearance is that your application is reported as consuming less memory in the Task Manager (simply because less of it happens to be resident right now). Don’t be misled–it is still just as big as it was before you minimized it, but now more of it is in your swap file instead of in your RAM chips.