Lenovo System x3750 M4 Installation And Service Manual page 44

The following table describes the jumpers on the system board.
Table 2. System-board jumpers
Jumper number
J71
J86
J115
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 recovery jumper 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 x3750 M4 Installation and Service Guide
Force NMI
button
Jumper name
UEFI boot recovery jumper
IMM low security jumper
IMM recovery jumper
SW7
switch block
IMM low security
jumper (J86 )
IMM recovery
jumper (J115 )
UEFI boot
recovery
jumper (J71)
Light path
button
Jumper setting
• Pins 1 and 2: (default) Loads the
primary UEFI firmware ROM page.
• Pins 2 and 3: Loads the secondary
(backup) UEFI firmware ROM
page.
• Pins 1 and 2: Removes the security
check, allowing unsigned IMM2
firmware.
• Pins 2 and 3: (default) Allows
only signed IMM2 firmware to be
flashed.
• Pins 1 and 2: (default) Loads the
primary IMM firmware ROM page.
• Pins 2 and 3: Loads the secondary
(backup) IMM firmware ROM page.