You may have seen issues on Windows 2012 server, where even after the users have disconnected from the server, their session is still consuming the memory. When you open task manager, you would see the session manager of the disconnected session taking huge amount of memory.
This happens when people with disconnected sessions are member of the Administrators group and logs on to the computer. When a member of the local admin group logs onto the machine, server manager starts automatically and stays in the background. You can modify default opening behavior of the Server Manager and Initial Configuration Tasks windows by editing the following registry settings.
Do not open Server Manager at logon
0 to disable and open the window normally; 1 to enable and prevent the window from opening.
Do not open Initial Configuration Tasks at logon
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Server Manager\Initial Configuration Tasks
More information can be found in http://technet.microsoft.com/en-us/library/cc753319.aspx#BKMK_RunningRMT .
Happy Learning & Troubleshooting!!
Disclaimer: Everything here, is my personal opinion and is not read or approved by Microsoft before it is posted. No warranties or other guarantees will be offered as to the quality of the opinions or anything else offered here.