Should no be that high. I am running a AMD 64 3200+ and I have been testing the new beta 4.9.11 running 2 applications of it at one time on my cpu. With 2 applications I am only using 4% to 8% with peaks of 35%. My memory usage when minimized for both about 80mb. These numbers are better than what I got with 1 application of 4.8.1. My guess is a bad java install try uninstalling LimeWire then uninstall java. Then manually install java then reinstall LimeWire. The link below has links to java in it.
http://www.gnutellaforums.com/showth...threadid=36420
Later Grandpa