Access and Postgres question.

I am testing postgres 7.02 and ms-sql server as back ends to ms access. I 
created identical databases containing three tables with about 1.2 , 1.6 
and 3 million records each. The machine that is running SQL server is a 
dual pIII zeon machine with raid 0 and 512 megs of ram. The postgres 
machine is a dual pIII 500 with 256 megs of ram no raid but nice fast scsi 
drive running red hat. Given this scenario I do expect postgres to be 
slower then ms sql server. What I find very odd is that in some tasks it 
actually faster (very slightly) like when doing simple select * from table 
where primarykey=x. But when I do select * from very_big_table (I know it's 
not such a good idea) it is insanely slow. On one test the table with 1.2 
million records too 12 seconds in postgres and less then a second in sql 
server!. I suspect that this has something to do with the ODBC driver 
because I am having a hard time believing that postgres is that slow. I 
suspect that the MS-SQL server ODBC driver is not actually pulling up ALL 
the records but just a few at a time (and perhaps spinning off another 
thread to fetch the rest). Can anybody confirm this?
----------------------------------------------             Tim Uckun      Mobile Intelligence Unit.
----------------------------------------------   "There are some who call me TIM?"
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