A Error Messages and Indicators
The board reports POST errors in three ways:
•By sounding a beep code
•By lighting the diagnostic LEDs
•By displaying an error message on the monitor
BIOS Beep Codes
The BIOS beep codes are listed in Table 31. The BIOS also issues a beep code (one long tone followed by two short tones) during POST if the video configuration fails (a faulty video card or no card installed) or if an external ROM module does not properly checksum to zero.
Table 31. Beep Codes
Number of Beeps | Description |
1 | Refresh failure |
2 | Parity cannot be reset |
3 | First 64 K memory failure |
4 | Timer not operational |
5 | Processor failure (Reserved; not used) |
6 | 8042 GateA20 cannot be toggled (memory failure or not present) |
7 | Exception interrupt error |
8 | Display memory R/W error |
9 | (Reserved; not used) |
10 | CMOS Shutdown register test error |
11 | Invalid BIOS (such as, POST module not found) |
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