How to: Set a Fixed Amount of Memory (SQL Server Management Studio)
Use the two server memory options, min server memory and max server memory, to reconfigure the amount of memory (in megabytes) in the buffer pool used by an instance of SQL Server. By default, SQL Server can change its memory requirements dynamically based on available system resources. When configured with a min server memory setting, the buffer pool does not immediately acquire the amount of memory specified for the min server memory. For more information about how SQL Server acquires memory, see Effects of min and max server memory.
To set a fixed amount of memory
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.
Use the default settings to allow SQL Server to change its memory requirements dynamically based on available system resources. The default setting for min server memory is 0, and the default setting for max server memory is 2147483647 megabytes (MB). The minimum amount of memory you can specify for max server memory is 16 MB.