Lenovo System x3550 M4 Installation And Service Manual page 42

Figure 17. System-board switches, jumpers, and buttons
The following table describes the jumpers on the system board.
Table 2. System board jumpers
Jumper number
JP1
JP2
JP6
Notes:
1. If no jumper is present, the server responds as if the pins are set to the default.
2. Changing the position of the UEFI boot backup jumper (JP2) 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.
The following table describes the functions of the SW3 switch block on the system board.
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System x3550 M4 Installation and Service Guide
Jumper name
CMOS clear jumper
UEFI boot backup jumper
System TPM physical presence
jumper
Jumper setting
• Pins 1 and 2: Normal (default).
• Pins 2 and 3: Clears the real-time clock (RTC)
registry.
• 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.
• Pins 1 and 2: Normal (default).
• Pins 2 and 3: Indicates a physical presence to
the system TPM.