DwgInfoTip freeware.

To install run setup.exe.

Administrator rights are needed to install.

After installation log out and log in from Windows if the tooltip does not show up.

It may be needed to run either of the below files and merge to the registry too.
InfoTipReg current user 32-bit.reg
InfoTipReg current user 64-bit.reg
InfoTipReg32-bit.reg
InfoTipReg64-bit.reg

License agreement
http://www.jtbworld.com/license_agreement.htm

Copyright  2007-2012 by JTB World
http://www.jtbworld.com