Disconnect the power supply cables from the system board connectors. Disconnect the power supply cables from all adapter cards (some models) and from all drives.
Remove the power supply cables from the cable clips and ties.
Remove the five screws at the rear of the chassis that secure the power supply.
Depress the power supply latch (1). Slide the power supply assembly toward the front of the computer and remove it from the chassis.
Ensure that the new power supply is the correct replacement. Some power supplies automatically sense the voltage, some power supplies are voltage specific, and some power supplies have a voltage-selection switch. If there is a voltage-selection switch, use a ballpoint pen to slide the switch, if necessary.
Note: For models that have a switch:
v If the voltage supply range is 100-127 V AC, set the switch to 115 V.
v If the voltage supply range is 200-240 V AC, set the switch to 230 V.
Install the new power supply into the chassis so that the screw holes in the power supply align with those in the chassis. Note: Use only the screws provided by Lenovo.
Install and tighten the five screws at the rear of the chassis to secure the power supply. Reconnect all power supply cables to the drives, adapter cards, and the system board. Make sure to reconnect the power cable to the graphics cards that require an additional cable.