@ NT:

I don't actually use any picture boxes. All of the things are just drawn on the form.

@ BB:

Yes, I did read your edit. As for the cloke rate, it's actually not close to 1ms. That's just what the timer control is set at, as a minimum interval value. Given the time taken to process the animation, it actually takes a fair bit longer than 1 second. As for the amount of data, no one is going to sit for hours to watch this stuff but the model runs for a long time to see how it evolves with time. I want to be able to jump to any step from 1 to 200,000 or whatever and hit the play button There are also things in the model that might kick in at a certain step and such.

Anyway I'm home now and I have a bunch of tests to do. I'll let you know of the result.