Usually a difference between the actual installed amount of ram and that indicated is caused by the onboard graphics using it.
Normally I would expect a difference of 16, 32, 64 or possibly 128mbs.
101 is an unusual figure though and I thought that you had an AGP card
![Huh? ???](http://www.pc-pals.com/smf/Smileys/Smileys/huh.gif)