Lenovo ThinkPad W520 4284 Hardware Maintenance Manual page 102

• 1100 Keyboard bezel assembly
• 1110 Bluetooth daughter card (BDC-3.0)
• 1120 Backup battery
• 1130 Smart Card or Smart Card dummy spacer
• 1140 Speaker assembly
• 1150 Thermal module
• 1160 CPU
• 1170 LCD unit
• 1180 Base cover assembly
• 1190 I/O sub card
Important notices for RAID setting:
Before you replace the system board, make sure that you read Installing and configuring RAID, and have the
necessary information. After you replaced the system board, RAID mode is recovered as default. To confirm
the SATA mode setting, you can see the setting in ThinkPad Setup menu as follows:
Config ➙ Serial ATA (SATA) ➙ SATA Controller Mode Option ➙ RAID/Compatibility/AHCI
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, to make sure that the HDD Active
Protection still functions (see below).
Note: If the test shows that HDD Active Protection is not functioning, be sure to document the drop in any reject
report, and replace the system board.
• Avoid rough handling of any kind.
• At every point in the process, be sure not to drop or stack the system board.
• If you put a system board down, be sure to put it only on a padded surface such as an ESD mat or conductive
corrugated material.
After replacing the system board, run PC-Doctor for DOS to make sure that HDD Active Protection still functions. The
procedure is as follows:
1. Place the computer on a horizontal surface.
2. Run Diagnostics ➙ ThinkPad Devices ➙ HDD Active Protection Test.
Attention: Do not apply physical shock to the computer while the test is running.
Table 35. Location of major sensitive components on the system board
Following components soldered on the top side of the system board are extremely sensitive. When you service
the system board, avoid any kind of rough handling.
a
CPU
b
Accelerometer chip for the HDD Active Protection System™
c
PCH (Platform Controller Hub)
d
Graphics
d
Note: (Graphics) is only for the Switchable Graphics models and Workstation models. The system
board in Integrated Graphics models does not have this chip.
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ThinkPad T520, T520i, and W520 Hardware Maintenance Manual