Memory Utilization High in Production Server

Hi

My Company IT manager Send to us the below : [ SQL server 2005]

Currently our SQL production server handling 809440 pages, which required 6.5GB memory.

8KB_Pages Pages_in_KB Pages_in_MB

809440 6475520.000000 6323.750000000

Here below the page count for each database
Clean master 115
Dirty master 3
Clean tempdb 3737
Dirty tempdb 1208
Clean model 18
Dirty model 3
Clean msdb 1888
Dirty msdb 196
Clean testdb1 14369
Dirty testdb1 55
Clean testdb2 18723
Dirty testdb2 1018
Clean testdb3 121
Dirty testdb3 192
Clean testdb4 10884
Dirty testdb4 3
Clean testdb5 22
Dirty testdb5 3
Clean testdb6 1699
Dirty testdb6 4258
Clean testdb7 10458
Dirty testdb7 3
Clean testdb8 3584
Dirty testdb8 3
Clean testdb9 1021
Dirty testdb9 3
Clean testdb10 7552
Dirty testdb10 788
Clean testdb11 16487
Dirty testdb11 391
Clean testdb12 158
Dirty testdb12 3
Clean testdb13 20187
Dirty testdb13 1949
Clean testdb14 5533
Dirty testdb14 3
Clean testdb15 3430
Dirty testdb15 3
Clean testdb16 45734
Dirty testdb16 5
Clean testdb17 8043
Dirty testdb17 1052
Clean testdb18 27
Dirty testdb18 3 and etc


and They informed "Summary of Condition: Memory Utilization High".

So i have used the below query to check which db + table wise highly uses the buffer pool

SELECT count(*)AS cached_pages_count ,CASE database_id WHEN 32767 THEN 'ResourceDb' ELSE db_name(database_id) END AS Database_name FROM sys.dm_os_buffer_descriptors GROUP BY db_name(database_id) ,database_id ORDER BY cached_pages_count DESC

SELECT count(*)AS cached_pages_count ,name ,index_id FROM sys.dm_os_buffer_descriptors AS bd INNER JOIN ( SELECT object_name(object_id) AS name ,index_id ,allocation_unit_id FROM sys.allocation_units AS au INNER JOIN sys.partitions AS p ON au.container_id = p.hobt_id AND (au.type = 1 OR au.type = 3) UNION ALL SELECT object_name(object_id) AS name ,index_id, allocation_unit_id FROM sys.allocation_units AS au INNER JOIN sys.partitions AS p ON au.container_id = p.partition_id AND au.type = 2 ) AS obj ON bd.allocation_unit_id = obj.allocation_unit_id WHERE database_id = db_id() GROUP BY name, index_id ORDER BY cached_pages_count DESC


after that i dont know what are things i have to do. So please guide for my scenario. Or if i am going wrong Please guide me what are things i have to check and do.