SMM

from The Free On-line Dictionary of Computing (8 July 2008)

System Management Mode
SMM

   <hardware> (SMM) A reduced power consumption state provided by
   some {Intel} {microprocessors}.  When a {CPU} enters SMM it
   saves its current state in a special area of {static RAM}
   called SMRAM (System Management {RAM}) and then runs a
   program, also stored in SMRAM, the SMM handler.

   SMM is implemented in all {Intel} "SL" suffixed CPUs.  In June
   1993, Intel announced it was discontinuing its SL range and
   instead making all its current processors SL enhanced.

   See also {Auto Idle}.

   (1994-11-09)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

SMM
       System Management Mode (CPU)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

SMM
       System Manager's Manual (BSD, Unix)