Service manual

Chapter 10 Motherboard and Component Replacement 10-21
Note If the motherboard is being replaced, remove all DSIMMs and SBus card(s)
prior to removing the motherboard. Note the chassis slot location for each DSIMM
and SBus card prior to removal.
The disk drives must be disconnected from the motherboard prior to motherboard
removal.
If a motherboard component is being replaced, you do not need to remove all
DSIMMs and SBus card(s) prior to removing the motherboard.
Note The NVRAM/TOD clock contains the system unit host identification (ID)
and Ethernet address. If the same ID and Ethernet address are to be used on the
replacement motherboard, remove the NVRAM/TOD from the removed
motherboard and install it on the replacement motherboard after the replacement
motherboard is installed.
10.6.1 Removing a Motherboard
Caution Use an antistatic mat when working with the motherboard. An antistatic
mat contains the cushioning needed to protect the underside components to prevent
board flexing, and to provide antistatic protection.
1. Power off the system unit.
See Section 6.2 “Powering Off the System Unit” on page 6-2.
2. Disconnect all cables, excluding the power cable, from the back of the system or
server unit.
3. Remove the system unit cover.
See Section 7.1 “Removing the System Unit Cover” on page 7-1.
4. Attach a wrist strap.
See Section 7.2 “Attaching the Wrist Strap” on page 7-3.
Caution – Use proper ESD grounding techniques when handling components. Wear
an antistatic wrist strap and use an ESD-protected mat. Store ESD-sensitive
components in antistatic bags before placing it on any surface.
5. Depopulate the motherboard as follows: