On Windows Server 2003 systems configured like this we found that it's
best to explicitly reserve at least half a gig to the OS, otherwise SQL
Server takes more and more. Once we did that, many performance issues
went away. 1.7 for SQL may be starving your OS, as others have noted.

Carolyn J

<snip>
Server have 2GB of memory, at the moment, SQLServer is using 1.7GB and
the rest is used by the OS, I presumed. Users complaining that the
database seems to be slow. Can someone please advise where to start
looking?
</snip>

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