Tight VNC Optimization

As I begin to do more and more automation with Eggplant, I am running into more and more troubles with lag like symptoms.

The more graphics that the SUT has to do, the slower my response time gets. I have heard that there are some optimizations that can be done to Tight VNC. I have not found a list of settings here in the forums. Does anyone out there have a good list of settings that can help me improve my experience?

Window XP professional on SUT.
Running Tight VNC as a service.