2-24 Setup and Operation
Fatal errors that occur during POST are communicated through a series of beeps that are
repeated continuously. All beep code errors, except beep code 8, are fatal errors and do not
allow the system to continue to boot.
If beep codes occur during POST, check the items in the Problem Checklist (at the start of
this chapter), verify that all the hardware is set up properly and securely connected, and try
rebooting. If you still get a beep code, go to the section “If You Need Assistance” at the
end of this chapter.
Beep Codes are listed in the table that follows.
Table 2-5 Beep Codes
NUMBER
OF BEEPS
ERROR
DESCRIPTION
1
Refresh Failure
The memory refresh circuitry on
the motherboard is faulty.
2
Parity Error
Parity error in the first 64 KB of
memory.
3
Base 64 KB Memory
Failure
Memory failure in the first
64 KB.
4
Timer Not Operational
Memory failure in the first
64 KB of memory or Timer 1 on
the motherboard is not
functioning.
5
Processor Error
The CPU on the motherboard
generated an error.
6
8042 – Gate A20 Failure
The keyboard controller (8042)
may be bad. The BIOS cannot
switch to protected mode.
7
Processor Exception
Interrupt Error
The CPU generated an
exception interrupt.
8
Display Memory
Read/Write Error
The system video adapter is
either missing or its memory is
faulty. (This is not a fatal error.)
9
ROM Checksum Error
The ROM checksum value does
not match the value encoded in
the BIOS.
10
CMOS Shutdown
Register Read/Write
Error
The shutdown register for
CMOS RAM failed.
11
Cache Error/External
Cache Bad
The external cache is faulty.
