Thanks for your post. I did try this with the IMAC, but not with the Mac Pro. It doesn’t seem to make a difference with the IMAC. I know I will have to step up to the Mac Pro again to get the best performance so I figured I would try to see what specs you are using so I would have a chance to get the desired results. When I try to render a simple explosion using Particular, with nothing else in the comp., it takes forever to render This is the type of composition I am getting bogged down with:https://www.dropdrop.com/templates.php (the second one down on the left)