I know it's not what you want, but if you were to process the grid of videos into a single video, you would eliminate the slow down. The problem is that GameEx is taking all of the videos in the grid and rendering them at different than native resolutions. If you do this with a single video, it's not a big deal. BUT, if you try to do that with 9, 12, more! videos, it will result in a massive slowdown even for a fast system. The alternative is to re-encode your videos into whatever resolution they will show up in the grid. I don't know that this will make things perfectly smooth, but it will certainly reduce much of the workload the system has to do.