Tuning: Taking advantage of 2GB RAM

I have Postgres 6.5 running on a 4-cpu Linux server with 2GB RAM, however
it does not seem to be taking full advantage of the available memory, even
during large queries. How do I tell Postgres that more memory is available?

Brian

P.S. Yes, I know we should upgrade to 7, but it looks like we're moving
this application to Oracle soon.
--
Brian Baquiran <brianb@edsamail.com>
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