1160 System Board Assembly And Fan Assembly - Lenovo ThinkPad Edge E420s Hardware Maintenance Manual

Step Screw (quantity)
2
M2 × 4 mm, wafer-head, nylon-coated (1)

1160 System board assembly and fan assembly

Important notices for handling the system board:
When handling the system board, bear the following in mind.
• The system board has an accelerometer, which can be broken by applying several thousands of G-forces.
Note: Dropping a system board from a height of as little as 6 inches so that it falls flat on a hard bench can subject
the accelerometer to as much as 6,000 G's of shock.
• Be careful not to drop the system board on a bench top that has a hard surface, such as metal, wood, or composite.
• If a system board is dropped, you must test it, using PC-Doctor for DOS if the system supports PC-Doctor for
DOS, to make sure that the HDD Active Protection System™ still functions.
Note: If the test shows that the HDD Active Protection System is not functioning, be sure to document the drop
in any reject report, and replace the system board.
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Hardware Maintenance Manual
Torque
Color
Black 0.181 Nm
(1.85 kgfcm)