Lenovo System x3550 M3 Problem Determination And Service Manual page 395

Figure 16. System-board LEDs
• Remind button: Press this button to place the system-error LED on the front information panel into
Remind mode. By placing the system-error LED indicator in Remind mode, you acknowledge that you are
aware of the last failure but will not take immediate action to correct the problem. In Remind mode, the
system-error LED flashes rapidly until one of the following conditions occurs:
– All known errors are corrected.
– The server is restarted.
– A new error occurs, causing the system-error LED to be lit again.
• NMI button: The NMI button on the front panel will come on when this button is pressed. 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. It allows you to blue screen the server and take a memory
dump (use this button only when directed by the IBM service support).
• Checkpoint code display: This display provides a checkpoint code that indicates the point at which the
system stopped during the boot block and POST. A checkpoint code is either a byte or a word value that
is produced by UEFI. The display does not provide error codes or suggest components to be replaced.
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Chapter 3 Diagnostics
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