System-board switches

Use this information to locate the system-board switches.

The following illustration shows the location of the switch blocks on the system board.

Important:
  1. Before you change any switch settings or move any jumpers, turn off the compute node; then, disconnect all power cords and external cables. Review the information in Safety Information page, Installation Guidelines, Handling static-sensitive devices, and Power on the compute node.
  2. Any system-board switch or jumper block that is not shown in the illustrations in this document are reserved.
Figure 1. System board switches
System board switches
Table 1. System board switches
1 SW5 switch block 4 SW3 switch block
2 SW8 switch block 5 SW2 switch block
3 SW1 switch block  
Note: Any system-board switches or jumpers that are not described in this section are reserved.
Switch and jumper functions are as follows:
  • All jumpers on the system board are reserved and should be removed.
  • The following table describes the functions of the switches on switch block SW5.

    Table 2. System-board switch block SW1
    Switch number Description Definition
    SW1–1 ME recovery ME boots to recovery
    SW1–2 ME firmware security override For debug only.
    SW1–3 Power permission Changing this switch to the on position enables Power On
    SW1-4 BMC reset Changing this switch to the on position forces the compute node to reset the BMC.
  • The following table describes the functions of the switches on switch block SW5.

    Table 3. System-board switch block SW5
    Switch number Description Definition
    SW5-1 Password override The default position is Off. Changing this switch to the On position overrides the power-on password.
    SW5-2 Trusted Platform Module (TPM) physical presence The default position is Off. Changing this switch to the On position indicates a physical presence to the TPM.
    SW5-3 Real time clock (RTC) reset The default position is Off. Changing this switch to the On position resets the RTC. A momentary toggle is all that is required. To avoid excessive CMOS battery drain, do not leave this switch in the On position.
    SW5-4 Serial select The default position is Off (send the serial input output (SIO) to the front serial port). Changing this switch to the On position sends the BMC to the serial port.
  • The following table describes the functions of the switches on switch block SW8.

    Table 4. System-board switch block SW8
    Switch number Description Definition
    SW8-1 Boot backup XClarity Controller When the switch is in the default Off position, the compute node will boot by using the primary XClarity Controller firmware. When the switch is in the On position, the compute node will boot by using a backup of the XClarity Controller firmware.
    SW8-2 Boot backup UEFI The default position is Off. Changing this switch to the On position forces the compute node to boot from the backup UEFI image.
    SW8-3 iBMC force update The default position is Off. Changing this switch to the On position bypasses the operational firmware image and performs a BMC firmware update, if the normal firmware update procedure results in an inoperative BMC.
    Note: Use this switch only if the normal firmware update procedure fails and the operational firmware image is corrupted. Use of this switch disables normal baseboard management controller operation.
    SW8-4 Wake on LAN (WOL) disable Changing this switch to the On position disables WOL.