Quote from Big AAPL:
Ninja can be a bit of a pig when you start to put up multiple instances of charts, T&S, etc. However, I think that the most important item to monitor in the Win Task Manager is the PF usage. When you start approaching the limits of system RAM, IE will most likely be the first to suffer because it requires alot of bandwith. If your CPU usage is under 30 with all processes active, it means you have a fast CPU, it will not overcome a lack of RAM.
A blind guess says you would need 2g of RAM, What do you have now?