6.From the outside, rear of the computer, remove the three Torx screws that secure the power supply to the rear of the chassis.
7.From the inside of the chassis, press the release button at the front of the power supply (1).
8.Slide the power supply forward (2), and then lift it out of the chassis (3).
To install the power supply, reverse the removal procedure.
CAUTION: When installing the power supply cables, make sure they are properly positioned in the clip under the drive cage.
Power supply 123