Lenovo 7090, 9705, 9625, 9421, 9353, 9485, 9623, 7061, 3656 Replacing the heat sink and fan assembly

assemblies are voltage specific, and some power supply assemblies have a voltage-selection switch. If your computer has a voltage-selection switch, ensure that you set the voltage-selection switch of the new power supply assembly to match the voltage available at your electrical outlet. If necessary, use a ballpoint pen to slide the voltage-selection switch to a different position.

vIf the voltage supply range in your local country or region is 100–127 V AC, set the voltage-selection switch to 115 V.

vIf the voltage supply range in your local country or region is 200–240 V AC, set the voltage-selection switch to 230 V.

7.Install the new power supply assembly into the chassis so that the screw holes in the power supply assembly align with those in the chassis.

8.Install the four screws to secure the power supply assembly. Note: Use only screws provided by Lenovo.

9.Reconnect the power supply assembly connectors to the system board.

10.Reconnect a power supply assembly connector to each of the drives.

11.Go to “Completing the parts replacement” on page 45.

What to do next:

vTo work with another option, go to the appropriate section.

vTo complete the installation, go to “Completing the parts replacement” on page 45.

Replacing the heat sink and fan assembly

Attention

Do not open your computer or attempt any repair before reading and understanding the “Important safety information” in the ThinkCentre Safety and Warranty Guide that came with your computer. To obtain a copy of the ThinkCentre Safety and Warranty Guide, go to: http://www.lenovo.com/support

This section provides instructions on how to replace the heat sink and fan assembly.

CAUTION:

The heat sink and fan assembly might be very hot. Turn off the computer and wait three to five minutes to let the computer cool before removing the computer cover.

To replace the heat sink and fan assembly:

1.Remove all media from the drives and turn off all attached devices and the computer. Then, disconnect all power cords from electrical outlets and disconnect all cables that are connected to the computer.

2.Remove the computer cover. See “Removing the computer cover” on page 16.

3.Lay the computer on its side.

4.Locate the heat sink and fan assembly. See “Locating parts on the system board” on page 12.

Chapter 2. Installing or replacing hardware 25