Replacing The System Board - Lenovo ThinkCentre 3656 Hardware Maintenance Manual

This section provides information on how to remove and replace the power supply.
To remove or replace the power supply, do the following:
1. Remove the computer cover. See "Removing the cover" on page 68.
Note: For this procedure, it helps to lay the computer on its side.
2. Disconnect the power supply cables from the system board and from all drives.
3. Remove the four screws that secure the power supply at the rear of the chassis.
4. Lift the power supply out of the chassis.
5. If the power supply has a voltage-selection switch, ensure that it is set to match the voltage available
at the electrical outlet.
• If the voltage supply range in your local country or region is 100-127 V ac, set the switch to 115 V.
• If the voltage supply range in your local country or region is 200-240 V ac, set the switch to 230 V.
6. Install the new power supply into the chassis so that the screw holes in the power supply align with
those in the chassis.
7. Install the four screws to secure the power supply.
Note: Use only the screws provided by Lenovo.
8. Reconnect the power supply connectors to the system board. See "Locating parts on the system
board" on page 71.
9. Reconnect a power supply connector to each of the drives.
10. Go to "Completing the FRU replacement" on page 91.

Replacing the system board

CAUTION:
The heat sink and microprocessor might be very hot. Turn off the computer and wait
three to five minutes to let the computer cool before opening the computer cover.
Chapter 8 Replacing FRUs (Types 7061, 7090, 9353, 9421, 9485, 9623, 9625, 9705, 9786, 9795, 9935, 9946, 9953)
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