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Bootable CD-ROM Is Not Detected
Check the following:
Y
Is the BIOS set to allow the CD-ROM to be the first bootable device?
Error and Informational Messages
When you turn on the system, POST displays messages that provide information about the system.
If a failure occurs, POST emits beep codes that indicate errors in hardware, software, or firmware.
If POST can display a message on the video display screen, it causes the speaker to beep twice as
the message appears.
POST Codes and Countdown Codes
The BIOS indicates the current testing phase during POST after the video adapter has been
successfully initialized by outputting a 2-digit hex code to I/O location 80h. If a port-80h ISA
POST card is installed, it displays the 2-digit code on a pair of hex display LEDs.
Table 9.
Port-80 Codes
Normal Port
80 Codes
Beeps
02
12
24
04
06
18
08
C4
11
0E
0C
16
1-2-2-3
17
28
2A
2C
1-3-4-1
2E
1-3-4-3
2F
38
20
1-3-1-1
88
Error
Verify Real Mode
Restore processor control word during warm boot (only occurs on warm reboot)
Set ES segment register to 4GB
Get processor type
Initialize system hardware
8254 timer initialization
Initialize PCIset registers with initial POST values
Initialize system flags in CMOS
Load alternate registers with initial POST values
Initialize I/O
Initialize caches to initial POST values
BIOS ROM checksum
Turn cache off
Autosize DRAM
Clear 512K base RAM
RAM failure on address line xxxx*
RAM failure on data bits xxxx* of low byte of memory bus (1st 4 meg)
Initialize L2 cache if enabled in CMOS
Shadow system BIOS ROM
Test DRAM refresh
continued
Solving Problems
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