With the PS3 power switch in the off position, turn power switch back on while holding down Eject button. This mode allows you to clean out the dust inside the PS3. It works for Models CECHG and higher.
The following requires the power switch in the back to be on…
Hold Power button down for 6 seconds (while PS3 is on): turns off PS3.
Hold Eject button down for 6 seconds (while PS3 is on): force disc to eject.
Hold Eject button down for 12 seconds (while PS3 is on): reset Blu-ray.
Hold Power button down for two beeps (while PS3 is off): Reset video to lowest settings.
Hold Power button down for three beeps (while PS3 is off): Enter PS3 diagnostic mode (repeat procedure twice)
Hold PS button down on controller for 10 seconds: Turns off Sixaxis or Dualshock 3.