Control panel
Part number 3500733

The front panel printed circuit board (PCB), part number 6001534, contains the light-emitting diodes (LED) and buttons that are accessible from the front bezel. To replace the PCB, remove the connecting cable, and then lift the PCB up and away from the front of the chassis.

  1. Power LED - Glows green when the computer is turned on.

  2. Hard disk activity LED - Flashes green when data is read from or written to a hard disk.

  3. Non-maskable interrupt (NMI) switch - Allows a technician to generate an NMI to aid in troubleshooting the computer.

  4. Power supply 1 status LED - Glows green when the first power supply module is on and working correctly. Flashes when power from that module is interrupted. This LED is not used with the standard PS/2 power supply.

  5. Chassis intrusion detection switch - This alerts the hardware management software that the front bezel has been removed.

  6. Power supply 2 status LED - Glows green when the second power supply module is on and working correctly. Flashes when power from that module is interrupted. This LED is not used with the standard PS/2 power supply.

  7. Motherboard connector - This connects the control panel to the hardware management features on the motherboard.

  8. Power monitor connector - This connects the control panel to the power monitor board. This connection is only used with the optional N+1 redundant power supply.

  9. Reset switch

  10. Power switch

  11. Power supply alarm reset button - This button is accessible through a pinhole in the bezel. Use this button to silence the alarm if a redundant power supply fails or is removed. This button is not used with the standard PS/2 power supply.