Lenovo IdeaCentre B750 All-in-One - Manual (Page 52)

Step 9. Disconnect the fan power cable from the motherboard.
Step 10. Remove the three screws that secure the system fan to the heat-sink 1 and lift the system fan up
to remove it. 2
Step 11. To install the new system fan:
a. Place the new system fan into position, and secure it with the three screws.
b. Connect the fan power cables to the connector on the motherboard.
Step 12. Reattach the EMI cover, middle cover, optical drive, computer stand and the rear cover.
Replacing the heat-sink
Note: Turn off the computer and wait 3 to 5 minutes to let it cool down before removing the cover.
Note: It may be helpful to place the computer face-down on a soft flat surface for this procedure. Lenovo
recommends that you use a blanket, towel, or other soft cloth to protect the computer screen from scratches
or other damage.
To replace the heat-sink:
Step 1. Remove any media (disks, CDs, DVDs or memory cards) from the drives, shut down the operating
system, and turn off the computer and all attached devices.
Step 2. Unplug all power cords from electrical outlets.
Step 3. Disconnect all cables attached to the computer. This includes power cords, input/output (I/O)
cables, and any other cables that are connected to the computer. Refer to “Left and right view”
and “Rear view” for help with locating the various connectors.
Step 4. Remove the rear cover. Refer to “Removing the rear cover”.
Step 5. Remove the computer stand. Refer to “Removing the computer stand”.
Step 6. Remove the optical drive. Refer to “Replacing the optical drive”.
Step 7. Remove the middle cover. Refer to “Removing the middle cover”.
Step 8. Remove the EMI cover. Refer to “Removing the EMI cover”.
Step 9. Remove the system fans. Refer to “Replacing the system fans”.
46 IdeaCentre B750Hardware Maintenance Manual