hi,
Use the two server memory options, min server memory and max server memory, to reconfigure the amount of memory (in megabytes) managed by the SQL Server Memory Manager for an instance of SQL Server.
In Object Explorer, right-click a server and select Properties.
Click the Memory node.
Under Server Memory Options, enter the amount that you want for Minimum server memory and Maximum server memory.
You can also do it in T-SQL using the following commands (example):
exec sp_configure 'max server memory', 1024
reconfigure
for more
http://msdn.microsoft.com/en-us/library/ms178067.aspx[
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