Wendy, Mike, Kathy,

There is a setting in Java that is sometimes correlated with poor graphics performance.  I posted a version of lasers here to help us identify whether that is a factor:
http://www.colorado.edu/physics/phet/dev/lasers/4.04.06/

I don’t believe I have this problem on any of my 4 test machines, but perhaps you could run this experiment and let me know the results:
1. Download lasers.jar, launch-lasers-ddraw-allowed.bat and launch-lasers-noddraw.bat to the same folder (could be your desktop)
2. For each of the .bat files:
                a. Double click on the .bat file (should start the simulation, let me know if not)
                b. Choose “Options” -> “Profile”
                c. Set Clock Delay to 5.0 by dragging the slider to the left.
                d. report back the average value for “Frame Rate”
                e. also report the version of java you are using, available from “Help” -> “About”

I will collect your results and check for a correlation between the settings.

Thanks,
Sam Reid