Section 1C - PC Hardware Information

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Information in Part 1
1. Floppy Drive won't read second Disk
2. Microsoft's DMF 1.77 Floppy Disks
3. Delete any file
4. Run SCAN once a day
5. PC Response Times Compared
6. RAM Chip Speeds
7. RAM Chip Types
8. RAM Chip Part Numbers - Links to Manufacturers
9. CPU Voltages
10. Common Interrupts (listing)
11. Computer Bus Terms
12. Changing CMOS by Direct Editing

Information in Part 2
13. RS-232 Pin-outs and Signals
14. RS-232 Made Easy
15. Loop Back Plugs
16. Parallel Ports - SPP, EPP, ECP, and More
17. Sound Cable Fix (missing audio channel)
18. CD-ROM Drives and Audio Extraction
19. Quantex Secrets
20. Burning CDs so they are easier to read...
21.  Reset Gateway Keyboard
22. AMI Happy Birthday BIOS Virus

Information in Part 3
23. AMD Win-BIOS Beep Codes
24. AMI BIOS Beep Codes
25. AMI BIOS Beep Codes - Ver 2
26. Phoenix Ver 1 Beep Codes (286/386/486)
27. Phoenix Ver 4 Beep Codes
28. How much Video Memory Do You Need?
30. Compaq BIOS Note
31. Using PAUSE to see the BIOS Version
32. Flashing BIOS WARNING!

Subject:  AMD WINBIOS Beep Codes (Advanced Micro Devices)
Beeps  Error Message         Description               Resolution
~~~~  ~~~~~~~~~~~~~~~    ~~~~~~~~~~~~~~~~~~~~     ~~~~~~~~~~~~~~~~~~~~~~~~
 1   Refresh Failure     The memory refresh       Reseat the memory SIMMs.
                         circuitry is faulty.     If the system still beeps,
                                                   replace the memory.
 2   Parity Error        Parity error in the      Reseat the memory SIMMS.
                         base memory (the first   If the system still beeps,
                         64 KB block) of memory.  Reseat the memory.
 3   Base 64 KB          Memory failure in        Reseat the memory SIMMs.
     Memory Failure      first 64 KB.             If the system still beeps,
                                                  replace the memory.
 4   Timer Not           A memory failure in      The motherboard must be
     Operational         the first 64 KB of       replaced
                         memory, or Timer 1  
                         is not functioning.
 5   Processor error     The CPU generated an     The motherboard must be
     8042 - Gate A20     error.                   replaced.
 6   8042 - Gate A20     Cannot switch to         Try a different keyboard,
     Failure Processor   protected mode.          or replace the keyboard
     Exception                                    fuse if the keyboard has
     Interrupt Error                              one.
 7   Processor           The CPU on the CPU       The motherboard must
     Exception           Card generated an        be replaced.
     Interrupt Error     exception interrupt.
 8   Display Memory      The system video         There is a memory error
     Read/Write Error    adapter is either        on the video adaptor.
                         missing or its memory    Replaced the video adaptor
                         is faulty. This is not   or the RAM on the video 
                         a fatal error.           adaptor.
 9   ROM Checksum        The ROM checksum value   The BIOS ROM chip is bad.
     Error               does not match the       The system probably needs
                         value encoded in         a new BIOS ROM Chip.
10   CMOS Shutdown       The shutdown register    The motherboard must
     Register Read/      for CMOS RAM has         be replaced.
     Write Error         failed.
11    Cache memory bad -  The cache memory test    The motherboard must
      do not enable       failed. Cache memory     be replaced.
      cache               is disabled. Do not 
                          press  Ctrl/Alt/Shift <+> 
                          to enable cache memory.
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Subject:  American Megatrends, Inc. BIOS Beep Codes
    The following beep codes would be heard on power on.   
    All of these errors are hardware related, so call your  
    motherboard manufacturer or reseller for help in correcting 
    the problem.
  Beep Code         Meaning
     1              DRAM refresh failure
     2              Parity Circuit failure
     3              Base 64K RAM failure
     4              System Timer failure
     5              Processor failure
     6              Keyboard Controller Gate A20 error
     7              Virtual Mode Exception error
     8              Display Memory R/W Test failure
     9              ROM-BIOS Checksum failure
      All of these errors are codes reported by bios.

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Subject:  AMI BIOS Beep Codes - Ver 2
What do the beeps mean when my system boots, but nothing appears on the
screen?  Errors can occur during the POST (Power On Self Test), which 
is performed every time the system is powered on. Fatal errors, which 
prevent the system from continuing the boot process, are communicated 
through a series of audible beeps. The following list shows the beep 
codes and corresponding error messages for Intel-manufactured 
motherboards that use the AMI BIOS:
Beeps    Error Message           Description
1 long,  No video card found     Applies only to baseboards with 
2 short                          no on-board video.
1 long,  No Monitor connected    Applies only to baseboards with 
3 short                          an on-board video present.
1 long,  Video related failure   Other video beep codes may exist and are 
x short                          tied to specific video BIOS implementations
                                 Contact the vendor for details should the 
                                 need arise.
1        Refresh Failure         The memory refresh circuitry on the 
                                 baseboard is faulty.
2        Parity Error            Parity is not supported on this product, 
                                 will not occur.
3        Base 64KB Memory Fail   Memory failure in first 64 KB.
4        Timer Not Operational   Memory failure in first 64 KB of memory,
			         or Timer 1 on baseboard not functioning.
5        Processor Error         The CPU on the baseboard generated an error.
6        8042-Gate A20 Failure   Keyboard controller (8042) may be bad.
				 BIOS cannot switch to protected mode.
7        Processor Exception     The CPU generated an exception interrupt.
	 Interrupt Error
8        Display Memory Read/    The system video adapter is either missing 
	 Write Error             or its memory is faulty.  Not a fatal error.
9        ROM Checksum Error      ROM checksum value does not match the value 
                                 encoded in BIOS.
10       CMOS Shutdown Register  The shutdown register for CMOS RAM failed.
	 Read/Write Error
11       Cache Error/            The external cache is faulty.
	 External Cache Bad
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Subject:  Phoenix BIOS Beep Codes for 286/386/486 Computers
80h    Beep 
Value  Code   Error/Test Description
01h    none    80286 register test in-progress
02h    1-1-3   CMOS write/read test in-progress or failure
03h    1-1-4   BIOS ROM checksum in-progress or failure
04h    1-2-1   Programmable Interval Timer test in-progress or failure
05h    1-2-2   DMA initialization in-progress or failure
06h    1-2-3   DMA page register write/read test in-progress or fail
08h    1-3-1   RAM refresh verification in-progress or failure
09h    none    1st 64K RAM test in-progress
0Ah    1-3-3   1st 64K RAM chip or data line failure - multi-bit
0Bh    1-3-4   1st 64K RAM odd/even logic failure
0Ch    1-4-1   1st 64K RAM address line failure
0Dh    1-4-2   1st 64K RAM parity test in_progress or failure
10h    2-1-1   1st 64K RAM chip or data line failure - bit 0
11h    2-1-2   1st 64K RAM chip or data line failure - bit 1
12h    2-1-3   1st 64K RAM chip or data line failure - bit 2
13h    2-1-4   1st 64K RAM chip or data line failure - bit 3
14h    2-2-1   1st 64K RAM chip or data line failure - bit 4
15h    2-2-2   1st 64K RAM chip or data line failure - bit 5
16h    2-2-3   1st 64K RAM chip or data line failure - bit 6
17h    2-2-4   1st 64K RAM chip or data line failure - bit 7
18h    2-3-1   1st 64K RAM chip or data line failure - bit 8
19h    2-3-2   1st 64K RAM chip or data line failure - bit 9
1Ah    2-3-3   1st 64K RAM chip or data line failure - bit A
1Bh    2-3-4   1st 64K RAM chip or data line failure - bit B
1Ch    2-4-1   1st 64K RAM chip or data line failure - bit C
1Dh    2-4-2   1st 64K RAM chip or data line failure - bit D
1Eh    2-4-3   1st 64K RAM chip or data line failure - bit E
1Fh    2-4-4   1st 64K RAM chip or data line failure - bit F
20h    3-1-1   master DMA register test in-progress or failure
21h    3-1-2   slave DMA register test in-progress or failure
22h    3-1-3   master interrupt mask register test in-progress or fail
23h    3-1-4   slave interrupt mask register test in-progress or fail
25h    none    interrupt vector loading in-progress
27h    3-2-4   keyboard controller test in-progress or failure
28h    none    CMOS power-fail and checksum checks in-progress
29h    none    CMOS config info validation in-progress
2Bh    3-3-4   screen memory test in-progress or failure
2Ch    3-4-1   screen initialization in-progress or failure
2Dh    3-4-2   screen retrace tests in-progress or failure
2Eh    none    search for video ROM in-progress
30h    none    screen believed operable:
30h    none    screen believed running w/ video ROM
31h    none    monochromatic screen believed operable
32h    none    40-column color screen believed operable
33h    none    80-column color screen believed operable
34h    4-2-1   timer tick interrupt test in_progress or failure
35h    4-2-2   shutdown test in_progress or failure
36h    4-2-3   gate A20 failure
37h    4-2-4   unexpected interrupt in protected mode
38h    4-3-1   RAM test in_progress or failure above address 0FFFFh
3Ah    4-3-3   Interval timer channel 2 test in_progress or failure
3Bh    4-3-4   Time-Of-Day clock test in_progress or failure
3Ch    4-4-1   Serial port test test in_progress or failure
3Dh    4-4-2   Parallel port test test in_progress or failure
3Eh    4-4-3   Math Coprocessor test in_progress or failure
Error codes in the 50h range or beyond are chip set or custom 
platform specific, and will vary from system to system. Contact 
your system manufacturer for details. 
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Subject:  Phoenix BIOS Beep Codes for Version 4.x. 
This POST/BEEP code list is applicable only to PhoenixBIOS 4.x.
Beep      POST
code      code  Description/test point
1-1-1-3    02   Verify Real Mode
1-1-2-1    04   Get CPU type
1-1-2-3    06   Initialize system hardware
1-1-3-1    08   Initialize chipset registers with initial POST values
1-1-3-2    09   Set in POST flag
1-1-3-3    0A   Initialize CPU registers
1-1-4-1    0C   Initialize cache to initial POST values
1-1-4-3    0E   Initialize I/O
1-2-1-1    10   Initialize Power Management
1-2-1-2    11   Load alternate registers with initial POST values
1-2-1-3    12   Jump to UserPatch0
1-2-2-1    14   Initialize keyboard controller
1-2-2-3    16   BIOS ROM checksum
1-2-3-1    18   8254 timer initialization
1-2-3-3    1A   8237 DMA controller initialization
1-2-4-1    1C   Reset Programmable Interrupt Controller
1-3-1-1    20   Test DRAM refresh
1-3-1-3    22   Test 8742 Keyboard Controller
1-3-2-1    24   Set ES segment to register to 4 GB
1-3-3-1    28   Autosize DRAM
1-3-3-3    2A   Clear 512K base RAM
1-3-4-1    2C   Test 512 base address lines
1-3-4-3    2E   Test 512K base memory
1-4-1-3    32   Test CPU bus-clock frequency
1-4-2-4    37   Reinitialize the chipset
1-4-3-1    38   Shadow system BIOS ROM
1-4-3-2    39   Reinitialize the cache
1-4-3-3    3A   Autosize cache
1-4-4-1    3C   Configure advanced chipset registers
1-4-4-2    3D   Load alternate registers with CMOS values
2-1-1-1    40   Set Initial CPU speed
2-1-1-3    42   Initialize interrupt vectors
2-1-2-1    44   Initialize BIOS interrupts
2-1-2-3    46   Check ROM copyright notice
2-1-2-4    47   Initialize manager for PCI Options ROMs
2-1-3-1    48   Check video configuration against CMOS
2-1-3-2    49   Initialize PCI bus and devices
2-1-3-3    4A   Initialize all video adapters in system
2-1-4-1    4C   Shadow video BIOS ROM
2-1-4-3    4E   Display copyright notice
2-2-1-1    50   Display CPU type and speed
2-2-1-3    52   Test keyboard
2-2-2-1    54   Set key click if enabled
2-2-2-3    56   Enable keyboard
2-2-3-1    58   Test for unexpected interrupts
2-2-3-3    5A   Display prompt "Press F2 to enter SETUP"
2-2-4-1    5C   Test RAM between 512 and 640k
2-3-1-1    60   Test expanded memory
2-3-1-3    62   Test extended memory address lines
2-3-2-1    64   Jump to UserPatch1
2-3-2-3    66   Configure advanced cache registers
2-3-3-1    68   Enable external and CPU caches
2-3-3-3    6A   Display external cache size
2-3-4-1    6C   Display shadow message
2-3-4-3    6E   Display non-disposable segments
2-4-1-1    70   Display error messages
2-4-1-3    72   Check for configuration errors
2-4-2-1    74   Test real-time clock
2-4-2-3    76   Check for keyboard errors
2-4-4-1    7C   Set up hardware interrupts vectors
2-4-4-3    7E   Test coprocessor if present
3-1-1-1    80   Disable onboard I/O ports
3-1-1-3    82   Detect and install external RS232 ports
3-1-2-1    84   Detect and install external parallel ports
3-1-2-3    86   Re-initialize onboard I/O ports
3-1-3-1    88   Initialize BIOS Data Area
3-1-3-3    8A   Initialize Extended BIOS Data Area
3-1-4-1    8C   Initialize floppy controller
3-2-1-1    90   Initialize hard-disk controller
3-2-1-2    91   Initialize local-bus hard-disk controller
3-2-1-3    92   Jump to UserPatch2
3-2-2-1    94   Disable A20 address line
3-2-2-3    96   Clear huge ES segment register
3-2-3-1    98   Search for option ROMs
3-2-3-3    9A   Shadow option ROMs
3-2-4-1    9C   Set up Power Management
3-2-4-3    9E   Enable hardware interrupts
3-3-1-1    A0   Set time of day
3-3-1-3    A2   Check key lock
3-3-3-1    A8   Erase F2 prompt
3-3-3-3    AA   Scan for F2 key stroke
3-3-4-1    AC   Enter SETUP
3-3-4-3    AE   Clear in-POST flag
3-4-1-1    B0   Check for errors
3-4-1-3    B2   POST done--prepare to boot operating  system
3-4-2-1    B4   One beep
3-4-2-3    B6   Check password (optional)
3-4-3-1    B8   Clear global descriptor table
3-4-4-1    BC   Clear parity checkers
3-4-4-3    BE   Clear screen (optional)
3-4-4-4    BF   Check virus and backup reminders
4-1-1-1    C0   Try to boot with INT 19
4-2-1-1    D0   Interrupt handler error
4-2-1-3    D2   Unknown interrupt error
4-2-2-1    D4   Pending interrupt error
4-2-2-3    D6   Initialize option ROM error
4-2-3-1    D8   Shutdown error
4-2-3-3    DA   Extended Block Move
4-2-4-1    DC   Shutdown 10 error
4-3-1-3    E2   Initialize the chipset
4-3-1-4    E3   Initialize refresh counter
4-3-2-1    E4   Check for Forced Flash
4-3-2-2    E5   Check HW status of ROM
4-3-2-3    E6   BIOS ROM is OK
4-3-2-4    E7   Do a complete RAM test
4-3-3-1    E8   Do OEM initialization
4-3-3-2    E9   Initialize interrupt controller
4-3-3-3    EA   Read in bootstrap code
4-3-3-4    EB   Initialize all vectors
4-3-4-1    EC   Boot the Flash program
4-3-4-2    ED   Initialize the boot device
4-3-4-3    EE   Boot code was read OK
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Subject:  How much Video Memory Do You Really Need?  
Here's a Chart from Matrox...
2D is normal Windows operation, 3D is for Games.
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Subject:  Compaq BIOS Note

Compaq BIOS, download startup disk from Compaq for your model. To get unit to boot from floppy, go into Setup and select SET DEFAULTS. This will turn off the secondary IDE controller killing the CD-ROM Drive. In setup, goes to Drives ADVANCED, Enable Secondary Controller, might be a select of the Address and IRQ (15).

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Subject:  Using PAUSE to see the BIOS Version

Having trouble seeing the BIOS information as it flashes by?  Just hit the PAUSE key to stop the boot process.

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Subject:  Flashing BIOS Warning!

When Flashing the BIOS on a Mother Board be sure to “Disable the option to Copy BIOS to RAM” in setup before you flash the BIOS.  Failing to do so will permanently damage the Mother Board making it unusable.

 Most systems have this option active as it speeds up the system when calls are made to anything controlled by BIOS such as floppy drive or I/O ports.

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