Large PGA for a data warehouse on Windows 2003 advanced server(32 bit)

Dear List,  

I am developing a data warehouse using Oracle 10g R1 on Windows 2003 advanced server(32 bit). The server has 32gb of ram and ideally I'd like to allocate a good portion of it to the pga and not just db block buffers. As I understand it windows "sees" 4gb of ram, 2gb of which is for windows, 1gb which is used for db block buffers which can map to higher regions of memory for larger amounts of db block buffers, leaving only 1gb of memory for the sga and pga. I'd like to know if there is a way to use more of the ram for the pga, in the neighborhood of 4-6gb.  

My background is on the unix side, so please keep the switch to linux comments to a minimum. I do not have a choice in this matter.  

Thanks,  

Ken Naim

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