(VGN-B3VP) memory upgrade limit

Hi

I've got a sony laptop (VGN-B3VP) that I'd like to install some more
memory in. The laptop currently has 512mb, which is hard-wired into
the system board - and there's one slot available for expansion.

My question is, what is the largest capacity chip I can fit into
this? The crucial site says I can fit a 1GB module and the sony site
say's the the laptop supports 1GB max in total? Not too sure what to
believe.

Seems that sony advertises lower than expected limits on most of their
laptop, even though the chipsets they use are fairly standard and
capable of utilising more.

If anyone has any ideas that could help, would be very grateful.
Thanks in advance

Luke