how to increase performance of Postgre

Hi all,

My project ( web application) is using Postgre 8.1 and PHP 4.x (ADO
library to access database). And I would like to increase perfomance, so
I changed configuration follow this:
shared_buffers = 16000（Default = 1000）
wal_buffers = 64（Default = 8）
But this setting is not strong effect. Please show me other way or your
idea to resolve my problem. Thanks a lot.

Best regards,

-Javanesevn.