IBM 7940, Problem Determination And Service Manual

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Power-on password
jumper (J52)
BMC update
jumper (J34)
NMI switch (SW1)
Force power-on
jumper (J37)
BMC reset
jumper (J36) Boot block recovery
jumper (J51)
Wake on LAN
bypass jumper (J48)
Attention: Before you change any switch settings or move any jumpers, turn off
the server; then, disconnect all power cords and external cables. See the safety
information that begins on page “Safety” on page vii. Do not change settings or
move jumpers on any system-board switch or jumper blocks that are not shown in
this document.
To change the position of the power-on password jumper, complete the following
steps.
1. Review the safety information that begins on page “Safety” on page vii.
2. Turn off the server and peripheral devices and disconnect all power cords and
external cables; then, remove the cover (see “Removing the cover” on page 31).
3. Move the jumper on J52 from pins 1 and 2 (the default) to pins 2 and 3 to
bypass the power-on password check.
4. Replace the cover, connect the server to a monitor, and then connect it to a
power source.
5. Turn on the server and wait until POST is completed.
6. Turn off the server and disconnect all power cords and external cables; then,
remove the cover.
7. Move the jumper on J52 from pins 2 and 3 to pins 1 and 2.
8. Replace the cover, connect the server to a USB keyboard, monitor, USB mouse,
and peripheral devices; then, connect the server to a power source.
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IBM System x3455 Type 7940 and 7941: Problem Determination and Service Guide