The most common question that I hear these days is do we have support for 64 Bit mode for SPS 2003?
The answer is Yes, with SP 2 of SPS 2003 (applicable for WSS with SP2 as well - in WOW mode only) 64 Bit mode is supported. The support articles gives a step by step procedure for installing SPS 2003 SP2 in a 64 Bit windows environment : http://support.microsoft.com/kb/905854/en-us
And with the same SP2 you can connect the SPS to a SQL 2005 backend DB running either on a 32 Bit mode or a 64 Bit mode. The performance benefit that you get is outstanding (a hopping 59% in case of large farm!!). Form complete details of benefit using SQL 2005 above SQL 2000 review the performance benefit test results at http://office.microsoft.com/en-us/assistance/HA100993571033.aspx .
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