Friday 5 July 2013

Troubleshooting Boot Problems

1.0 BIOS Beep Codes
It is likely that the BIOS on your
system was made by either Award
or AMI. Today, the majority of
motherboards purchased for
upgrading come with an Award
BIOS, though there are a very few
that offer the AMI BIOS as an
alternative. While Phoenix used to
be very popular, it is now rarely
found in desktop systems. Award
became part of Phoenix in 1998.
The Award BIOS actually has only a
single defined beep code, which is
emitted when the video controller
cannot be initialized. This code is a
single beep, followed by three
short ‘chirps’ in rapid succession.
The short beeps can occur very
fast, and might sound like only two,
but by listening very carefully you
should be able to discern three of
them. If this signal is given, the
video card may not be seated
correctly, or it may actually be
defective. If reseating it does not
resolve the problem, try it in a
different card slot (if available). As
a final resort, the card may need
to be replaced.
One other code that is usually
given, but not officially defined by
Award, is a single long beep that is
repeated indefinitely. This generally
is emitted when the memory
refresh fails, which could be a bad
connection, bad slot or a bad
module. Once again, if reseating
the memory modules does not
correct the problem, try a different
slot or replace the module.
AMI defines a number of beep
codes, which are too numerous to
mention. If you have an AMI BIOS,
you can get most of the
information you need from the
AMI Homepage, under the ‘Tech
Support’ section. More information
about Award BIOS’, and additional
technical information can be found
on the Phoenix website . Other
good resources for BIOS
information are The PC Guide and
Wim’s BIOS Page .
1.1 No Video Splash Screen
Check that the power cord is
plugged into both the wall and the
power supply (really!!). If the
power supply fan doesn’t spin,
either it is not plugged in, or the
power supply is bad.
Check that the 12V power plugs
from the power supply are
properly plugged in. There are
usually two plugs – P8 and P9. The
two black wires on each plug
should be next to each other (four
black wires in a row). If this is the
problem, the power supply fan will
spin but the hard drive will not
spin up.
Take out and reseat the CPU,
Memory and Video card. If any one
of these is not making good
contact, the system will not boot.
If you have your speaker
connected, you will hear a beep
code if this is your problem (check
the documentation for your BIOS
to interpret beep codes).
Make sure that your IDE cable (if
installed) is connected with the
colored edge (pin 1) aligned with
pin 1 on the motherboard
connector. If you don’t hear the
hard drive spin up, that would be a
good clue the cable is backwards.
Check the jumper settings for the
CPU – both bus speed and clock
multiplier. If this is set incorrectly,
the system may not boot at all.
Make sure that there is no metal-
to-metal contact between the
board and the case, except at
‘designated’ points. This means that
the small brass hex nuts that the
board is held on with should NOT
be used as a standoff if there is no
corresponding hole for it. Doing
this will cause a short between the
board and the case, thereby
keeping the system from getting
the proper power, and possibly
damaging the motherboard.
Check that you have filled the
entire memory bank with memory.
Pentium/Pentium Pro
motherboards use two SIMMS of
the same type (both 8MB or both
16MB), or one DIMM. They also
must be in the same bank – which
means they need to be right next
to each other in even/odd slots
(i.e., 0/1 or 2/3, not 0/2 or 1/2).
Once again, check your
motherboard manual for
requirements in regards to which
slots must be filled first, and how
many slots make a bank.
If you didn’t do this first, take the
motherboard completely out of the
case (if you have it installed before
trying to boot it) and put it onto a
non-conductive surface (perhaps
the top of the box it came in).
Position it such that you can
connect the power supply plugs,
then insert the CPU, memory and
video card. Give it one more
‘power on’ attempt. If it now
boots, then you had some unknown
contact with the case (grounded
improperly). This step shouldn’t be
too intrusive, as you were probably
going to take it out and ship it
back to the supplier anyways.
1.2 System Does Not Complete
POST
Check that you don’t have
mismatched memory in your SIMM
slots. Remember, Pentiums require
two SIMMs to make a full memory
bank (but only one DIMM), and
they must be like configuration
(two 8MB or two 16MB, etc). Also
consider that you may have a bad
memory module if you are buying
‘generic’ modules. A good clue for
this is if the system only counts up
to 640K, then locks.
If your motherboard has cache on
board (Socket 5 or 7), check that
the L2 cache jumper (if applicable)
is set properly. Again, read the
manual. Note how much cache is
soldered on board (if any), and
how much is on any COAST
module. Do NOT assume that you
know how much cache is plugged
in – CHECK IT OUT.
If the motherboard has cache on
board, turn off External (L2) cache
in the BIOS. You may have
defective L2 cache, which means
the board will need to be replaced
(or the COAST module, whichever
applies)
Set your BIOS to factory defaults
(there is usually a couple of menu
choices for BIOS defaults and
SETUP defaults). It is possible you
have a conflict in your BIOS
settings.
Eliminate all unnecessary devices
and device drivers, then boot
again. You may have an IRQ or
DMA conflict, or some drivers may
be conflicting with each other. You
can eliminate ‘boot up’ device
drivers by placing an REM
statement in front of the driver in
the CONFIG.SYS file, which makes
it a remark statement. If this turns
out to be the problem, re-
introduce devices or drivers one at
a time until you determine which
one is causing the lockup.
1.3 Operating System not Found or
Boot Device Missing
Make sure your IDE cable is
plugged in properly. The colored
edge of the ribbon cable should be
plugged into pin 1 of both the
motherboard connector and the
hard drive.
Make sure both ends of the ribbon
cable are seated firmly. A loose
cable may allow the drive to be
detected, but unreadable.
Be sure you have the 5V power
connector plugged into the drive
securely.
Check that the BIOS settings are
correct for the hard drive. If the
BIOS does not have an auto-detect
feature, you will need to find out
the correct Cyl-Head-Sect
information so the operating
system can read the drive
properly.
Check if you have a boot manager
(such as On-Track) to support
540MB+ hard drives on a non-LBA
system. This software is
incompatible with hardware LBA
and will render your device
unreadable. In this case, you need
to set the CMOS parameters for the
hard drive to NORMAL (not LBA). If
you want to use LBA mode, you will
have to reformat the drive as
follows:
Use the FDISK command with the /
MBR option. This will remove the
software from the master boot
record.
Use FDISK to repartition your
system
Use the FORMAT d: /S to format
the drive and transfer the
operating system
Re-install the complete operating
system and applications, or restore
from your latest backup.
Use the command FDISK /MBR (do
NOT use this if you have disk
manager software on your drive to
emulate LBA mode on 540MB+
hard drives). This will re-create
your master boot record without
destroying any data on the drive
(be absolutely sure to use the /
MBR switch). When you issue this
command, you will get no response
back other than a blinking cursor
and prompt.
Use FDISK to set the boot partition
active.
1.4 Keyboard Isn’t Recognized
This is usually the result of the
keylock pins being jumpered. On
most motherboards there is a 5-
pin connector labeled ‘Keylock’.
Pins 1 and 3 are the Power LED,
while pins 4 & 5 are the keylock.
You may have accidentally
jumpered the wrong pins and
locked the keyboard out.
1.5 Slave IDE Drive Not Detected
(Hard Drive or CDROM)
Be sure that the Primary IDE drive
is jumpered for MASTER, and the
Slave drive is jumpered for SLAVE.
Some drives have the same setting
for SINGLE and MASTER, but most
have a separate setting. If the
Primary drive is set to SINGLE, the
Slave drive may not be detected.
Check the ribbon cable to ensure
that the colored edge is plugged
into pin 1 on the Slave drive.
Make sure the ribbon cable is
seated properly at all connection
points.
Be sure that the 5V power plug is
connected securely.

«Previous page

By Dean Kent

No comments:

Post a Comment