IBM System x3400 Type 7973, Problem Determination And Service Manual

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System-board switches
The following illustration shows the switches on the system board.
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2
3
4
5
6
7
8
9
10
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12
DIMM LEDs
Boot block/Clear CMOS
The following table describes the function of each switch on the system board.
Table 3. System board switches
Switch number Description
1 Boot block:
v When this switch is on 1 , this is normal mode.
v When this switch is toggled to On , this enables the
system to recover if the BIOS code becomes damaged.
See “Recovering from a BIOS update failure” on page 72
for more information.
2 Clear CMOS:
v
When this switch is on 2, this keeps the CMOS data.
This is normal mode.
v When this switch is toggled to On , this clears the CMOS
data, which clears the power-on password and
administrator password.
Chapter 1. Introduction
15