Help how to tune-up my Database

Hi,

I am a newbie here and just starting to use postgresql. My
problems is how to tune up my server because it its too slow.

We just ported from DBF to postgresql.

This is my PC specs: P4, 512Ram, Linux 9

Because I am working in a statistical organization we have a very large data
volume

These are my data:

Table 1 with 60 million data but only with 10 fields

Table 2 with 30 million data with 15 fields

Table 3 with 30 million data with 10 fields

I will only use this server for querying ... I already read and apply those
articles found in the archives section but still the performance is not
good.

I am planning to add another 512 RAM .Another question is how to calculate
shared_buffer size ..

Thanks a lot and hoping for your kind answers ..

Michael Puncia

Philippines