dirty power

from Jargon File (4.4.4, 14 Aug 2003)

dirty power
 n.

   Electrical mains voltage that is unfriendly to the delicate innards of
   computers. Spikes, {drop-outs}, average voltage significantly higher
   or lower than nominal, or just plain noise can all cause problems of
   varying subtlety and severity (these are collectively known as {power
   hit}s).

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

dirty power

   Electrical mains voltage that is unfriendly to the delicate
   innards of computers.  Spikes, {drop-outs}, average voltage
   significantly higher or lower than nominal, or just plain
   noise can all cause problems of varying subtlety and severity
   (these are collectively known as {power hits}).

   [{Jargon File}]

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