Hey Blaster,
First of all, welcome to Simviation

I'm sorry to hear about your problem. As I read the title, I immediately thought that BUFFERPOOLS would fix the problem. Unfortunately, that's not working for you. I would also have recommended the FPS_Limiter, but you've already tried that. Besides these tweaks, there's not much I can say besides play around with your TBM setting.
Either way, let's take a look at your FSX settings to make sure everything is where it needs to be for your hardware. Post your settings (remember to upload pics to the simviation site first,
here). I would also recommend starting with a new fsx.cfg file (delete it, and run FSX to write a new one) and test with different TBM numbers, then with different BUFFERPOOLS. Only those two tweaks.
There's not much I can do to help you, so we'll have to wait until someone more knowledgable like Nick jumps in here to check it out.
Best of luck,
Andy

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