Ahh I had the same problems a few days ago. Check
http://www.linuxquestions.org/questi...045#post820045 for a possible solution. Works charms for me
Or if you don't want to reinstall, go to
kde menu/configuration/configure your computer, go to the
boot section and hit next. Once in the advanced tab where you get all the possible options, select the one you use to boot and hit
modify. In the append box, add
noapic nolapic, then save everything and reboot. You should stop having those madening lock ups