89 
4  Error Messages and Beep Codes 
What This Chapter Contains 
4.1  Speaker........................................................................................................................89 
4.2  BIOS Beep Codes........................................................................................................89 
4.3  BIOS Error Messages ..................................................................................................89 
4.4  Port 80h POST Codes .................................................................................................90 
4.1 Speaker 
The board-mounted speaker provides audible error code (beep code) information during POST. 
 
For information about   Refer to 
The location of the onboard speaker  Figure 1, page 12 
4.2  BIOS Beep Codes 
Whenever a recoverable error occurs during POST, the BIOS displays an error message describing 
the problem (see Table 46).   
Table 46.  Beep Codes 
Type   Pattern  Frequency 
Memory error  Three long beeps  1280 Hz 
Thermal warning  Four alternating beeps:   
High tone, low tone, high tone, low tone 
High tone:  2000 Hz 
Low tone:  1600 Hz 
4.3  BIOS Error Messages 
Table 47 lists the error messages and provides a brief description of each. 
Table 47.  BIOS Error Messages 
Error Message  Explanation 
CMOS Battery Low  The battery may be losing power.  Replace the battery soon. 
CMOS Checksum Bad  The CMOS checksum is incorrect.  CMOS memory may have 
been corrupted.  Run Setup to reset values. 
Memory Size Decreased  Memory size has decreased since the last boot.  If no memory was 
removed then memory may be bad. 
No Boot Device Available  System did not find a device to boot.