Windows memory use question

In 2k & XP the Windows Task Manager has tow tabs showing how much memory is in use: the Processes and Performance tabs.

How come the number shown in PF Usage portion of the Performance tab is always greater than the sum of the Mem Usage column from the Processes tab? My Processes (at the moment) add up to about 510MB, and Performance lists 819-820 MB? I would think these two would tie out. What am I missing?

-Zeke

mem usage by default = just physical. goto the process tab -> view -> select columns -> check virtual memory size -> ok. add those two together, and you have a winner.

Thank you so much. I never even knew those other options existed.

-Chris