I don't understand why some work units finish in 3 hours others take 4
hours.  I'm barely using the computer and not playing any games and I
get between 3 and 4 hours to do one WU on a 2.8 Ghz Northwood 533 FSB.
I disabled indexing service, anything that may be using CPU cycles?
This is a fresh install of XP and I doubt the indexing service would
cause an hour difference.