I just got a new Dell that arrived with a virus-like problem - a very busy CPU with very little time left over to do anything useful. Too lazy to ship it back to Dell, I started to try some fixes. I shut down anti-virus and other programs that loaded in at start-up with little, if any, improvement. The CPU often (but not always) stayed at 99% on "system." Finally I realized that "system" meant Windows. Like others suggested in an earlier discussion on this topic, I went to www.blackviper.com/WinXP/servicecfg.htm and I shut down every WIN XP Home function recommended in the "Safe" column. (Simply run "services.msc" and use the properties icon to make the changes.) Fixed!!! I then noticed that the task manager still showed 13% CPU usage when it should have been 0%. I selected the faster plot option and it showed an alternating string of 0% and 25% for the CPU working the system. It alternated in perfect sync forever...hmmm, of course! - it's just the task manager itself taking readings of the system performance. The thing I can't figure out is why only certain computers (a small percentage) have a problem running all the background functions (like the troublesome indexing) that Windows likes to run.