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System-board switches, jumpers, and buttons

The following illustrations show the location of the switches, jumpers, and buttons on the server.

Note
If there is a clear protective sticker on the top of the switch blocks, you must remove and discard it to access the switches.
Figure 1. System-board switches, jumpers, and buttons
System-board switches, jumpers, and buttons
Figure 2. System-board switches, jumpers, and buttons: for machine type 8871–AC3
System-board switches, jumpers, and buttons

The following table describes the jumpers on the system board.

Table 1. System board jumpers.

This is the system board jumpers table with three column headings. This first column is jumper number. The second column is jumper name. The third column is jumper setting.

Jumper numberJumper nameJumper setting
J7System TPM physical presence jumper
  • Pins 1 and 2: Normal (default).
  • Pins 2 and 3: Indicates a physical presence to the system TPM.
J11CMOS clear jumper
  • Pins 1 and 2: Normal (default).
  • Pins 2 and 3: Clears the real-time clock (RTC) registry.
J15UEFI 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.
Note
  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 (J15) 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 SW6 switch block on the system board.
Table 2. System board SW6 switch block definition.

Three column table for documenting the switch number, default position and corresponding description.

Switch numberDefault positionDescription
1OffReserved.
2OffPower-on password override. Changing the position of this switch bypasses the power-on password check the next time the server is turned on and starts the Setup Utility so that you can change or delete the power-on password. You do not have to move the switch back to the default position after the power-on password in overridden.

Changing the position of this switch does not affect the administrator password check if an administrator password is set.

3OffReserved.
4OffReserved.
5OffReserved.
6OffReserved.
Important
  1. Before you change any switch settings or move any jumpers, turn off the server; then, disconnect all power cords and external cables. Review the information in Safety, Installation guidelines, Handling static-sensitive devices, and Turning off the server.
  2. Any system-board switch or jumper block that is not shown in the illustrations in this document are reserved.

The following table describes the functions of the button on the system board.

Table 3. Button on the server.

Two column table for documenting the button name and corresponding function.

Button nameFunction
Force NMI buttonThis button is on the rear of the server. Press this button to force a nonmaskable interrupt to the microprocessor. You might have to use a pen or the end of a straightened paper clip to press the button. You can also use it to force a blue-screen memory dump (use this button only when you are directed to do so by Lenovo Support).