Clone computer with Intel D845WN Motherboard

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My friend has a clone computer with an Intel D845WN Motherboard.
Recently, his system became unable to start. Power supply is working.
but there is no boot-up or bios info showing up on the monitor. The
monitor is tested and works.. His hard drive works as we put his into
my machine and it booted up. ( which allowed him to recover his
data.)  He replaced his bios battery but to no avail.
Could this be a bios problem. If so is there a way of checking or
flashing the bios to restore it?
Any suggestions you have would be greatly appreciated.

Re: Clone computer with Intel D845WN Motherboard

sw wrote:
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Cards like the following, can be plugged into the PCI slot
nearest to the processor socket. The card has a two digit
display. It displays a hexadecimal code, from 0x00 to 0xFF.
These cards are available on Ebay, and ship from Hong Kong,
and that is where you get the cheapest of these.

When the display first powers up, the display will either
show 00 or it could show FF. Those are "uninitialized" values.

As the BIOS starts to run, the BIOS contains code to write
to the PCI display card. For example, it could write "01" to
the display, if subroutine 01 was about to run.

Thus, the code is not an "error" code, but more of a
"progress" code. The numbers will flicker rapidly, when
a BIOS is working properly.

If a BIOS gets "stuck", then the display will also freeze
with the last written value on it. Say the value showed
"56". You'd consult a table of codes for the motherboard,
to determine what "subroutine 56" does. (See page 121 of the
manual, which is linked at the bottom of this post.)

The main benefit of such a card, is as a go/no-go display.
If the motherboard is broken, the display might stay at
the initial 00 or FF value indefinitely. That would tell
you no BIOS was executing. But it doesn't tell you why
that is. For example, the BIOS chip itself could be
erased or broken. Or, the main processor chip could be
broken. Or the Northbridge, through which passes the data,
could be broken. There are lots of causes for a failure
to execute BIOS code, and that display device will not
help you do a detailed diagnosis. (The card is not a
good investment, unless it is really cheap.)

If the BIOS chip is held in a socket, and the chip is
removable, you can buy a new chip from .
There are other companies, similar to badflash, that perform
the same service. You tell the company, what the BIOS chip
part number is ("PMC1234" or whatever), and you also tell
the company, where they can find a copy of the latest
BIOS file. You send them $25 to $30, and they send you
a chip in return. You snap the chip into the socket,
and then try to get the board to POST.

See section 2.9.2 on page 73, as Intel has more jumper options
than other motherboards. As far as I know, the "recovery" position
is a boot block loader, and maybe that can be used to reflash
the BIOS.

Section 3.7 on page 91, details what to expect. You offer
the BIOS file on a floppy diskette, when the jumper is
set for recovery. If the "boot block" is functional in
the BIOS chip, and is being read, then the BIOS will
attempt to read the floppy drive. The computer monitor
will remain black, because there is no video driver. You
have to judge the completion of a BIOS reflash, by the
noise (beeps) and lack of floppy activity. This should
not be attempted, if the computer has recently displayed
signs of instability (crashes a lot), because if it
crashes in the middle of a flash, there is no guarantee
you'd get a second opportunity to flash it.

If the procedure on page 91 fails, you can pay the $25
to $30, and get a new BIOS chip. As long as the chip can be
removed from the (brown colored) PLCC socket, you can put
another one in place. If the chip is soldered (as it is on
a small number of boards), then removal is much more difficult,
and can result in permanent damage to the motherboard.

The total expense, in swapping in replacement components,
using the PCI POST card, and so on, makes diagnostic work
an expensive proposition for a home builder. And it still
might turn out, that the motherboard is bad (or the power
supply). At least the power supply, you can check the
voltages with a multimeter, if you happen to own a

(Power supply spec - see page 30)

That motherboard has two power connectors. It has
"ATX12V", a 2x2 square connector with two yellow wires and
two black wires. That is what powers the processor. The
main power connector, the one with a lot more wires on it,
is used to power everything except the processor on the
motherboard. Make sure both connectors are seated.


Re: Clone computer with Intel D845WN Motherboard

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Check for bad RAM.  Next most likely problem is a belly-up motherboard.  JG

Re: Clone computer with Intel D845WN Motherboard

sw wrote:
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Try removing everything from the motherboard except the Power Supply, CPU,
CPU fan, and the monitor. (you did check the CPU fan, right?)  Then power on
the computer.  If nothing shows up on the monitor, no beeping from the
motherboard (complaining of no ram) then you have either a bad motherboard,
CPU chip, or power supply.

Remember power supplies provide more than one voltage.  a Chassis fan
working does not guarantee the CPU is getting the proper voltages it needs
from the power supply.

Re: Clone computer with Intel D845WN Motherboard

On Mon, 22 Jun 2009 14:44:02 -0700 (PDT), sw

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To what extent have you tested or determined that the power
supply is working?  When you wrote "clone computer", it
makes me think of a lower priced system built by a computer

I am asking because often they use poor quality PSU to cut
costs, PSU that are likely to have capacitor failures.  In
such a case, the PSU might appear to run for awhile, allow
fans and LEDs to get power, but not be stable enough to
power a system even if the voltages still measure roughly
the correct value.

If it is using such a questionable PSU I would unplug it
from AC for a few minutes, then pull and open it for
inspection.  Typical capacitor failure results in vented
tops or leaky residue on the top or bottom of the larger
capacitors near where the wiring harness connects to the
circuit board, or a bit smaller diameter 5VSB capacitor
often closer to the exhaust vents.

Beyond the PCI POST card suggestion Paul made, the remaining
typical troubleshooting would involve reducing the parts to
only what is necessary for POST, meaning PSU, motherboard,
CPU, heatsink/fan, video card (though that board probably
has integrated video so I mean that), and 1 memory module.

Next clear CMOS, even if you had already, with AC power
disconnected.  If the system still fails to POST you can
swap known good parts into it or vice-versa, swap one part
at a time from it into a working system.

Lastly, considering the age of the system, it might be a
good time to do some upgrades.  If some time is spend online
looking for deals, a reasonable PSU/motherboard/CPU/4GB
memory can be had for about $200 delivered, meaning the case
and drives would be reused.  That way you significantly
upgrade the system as well as replacing all questionable
parts instead of 'sinking nearly as much money into only a
repair, as the system might be worth in total at this point.

Re: Clone computer with Intel D845WN Motherboard

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These were all good tips, thankyou for your time and ideas.

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