Ohhh, Bobby, you need to do some tweeking.
first make sure that SETI is set for blanking,its in the setup screen, also with a 450 it can be set to run all the time, unless you are crunching something else.
Also go to
http://www.iarsn.com/ and download Task2000, it allows you look at your resources and see whats stealing all of your cpu time.