Lenovo System x3550 M5, Installation And Service Manual

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UEFI boot backup
jumper (J13)
System TPM physical
presence switch (SW11)
Clear CMOS jumper (J11)
NMI button
1
2
SW3 switch
block
On
Off
4 8 3 7 2 6 1 5
3
2
1
1
2
3
On Off
Figure 27. System-board switches, jumpers, and buttons
The following table describes the jumpers on the system board.
Table 1. System board jumpers
Jumper number Jumper name Jumper setting
J11 Clear CMOS jumper • Pins 1 and 2: Normal (default).
• Pins 2 and 3: Clears the real-time clock (RTC)
registry.
J13 UEFI boot backup jumper • Pins 1 and 2: Normal (default). Loads the
primary server firmware ROM page.
• Pins 2 and 3: Loads the secondary (backup)
server firmware ROM page.
Notes:
• If no jumper is present, the server responds as if the pins are set to the default.
• Changing the position of the UEFI boot backup jumper (J13) from pins 1 and 2 to pins 2 and 3 before the server is
turned on alters which flash ROM page is loaded. Do not change the jumper pin position after the server is
turned on. This can cause an unpredictable problem.
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Lenovo System x3550 M5 Installation and Service Guide