Hi, if it's lsass.exe, then check out this article (http://www.fileinspect.com/fileinfo/lsass-exe/).

Here's a good article on how to fix high svchost.exe CPU usage - http://www.fileinspect.com/fileinfo/svchost-exe/. It's quite long, so can't post ll of it here. Hope this helps.

Might be a Windows Explorer problem. Check out this article (http://www.fileinspect.com/fileinfo/explorer-exe/) - maybe you will find a fix there.