67
4 Error Messages and Beep Codes

What This Chapter Contains

4.1 Speaker......................................................................................... 67
4.2 BIOS Beep Codes ............................................................................67
4.3 BIOS Error Messages ....................................................................... 67
4.4 Port 80h POST Codes....................................................................... 68

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 34).
Table 34.
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 35 lists the error messages and provides a brief description of each.
Table 35. 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.