Hi Sue, I have done a SUM on pages_kb in dm_os_memory_clerks, which adds up the space taken by all clerk types.  The total is 22GB.  SQL Server is using 51GB, and PLE is 51, so that's why I am wondering where the rest of the RAM has gone.

Hi Subramanian, do you have any scripts, there is a lot of information in those tables and I am not sure what I am looking for.