K8V SE Deluxe Problem?

  • Thread starter Thread starter Richard&Sue
  • Start date Start date
R

Richard&Sue

Hi, I have just purchased a new PC which has the K8V SE Deluxe m/b
installed.

The problems I have had are that after only a couple of times using the
machine on the first day the bios lost its settings and I had to go in by
pressing F1 and reset the date, time etc. After which it worked ok. It does
do a short beep after it loads the via sata driver and then continues to
load Windows.

This morning when I turned it on it said that it couldn't find the via sata
drive connected, so I restarted it and all worked fine. I downloaded the
current 1001 bios and used the EZ Flash update using Ctrl + F2 when booting
thinking that maybe the bios was faulty and reprogramming it would be a good
idea! It read the data from the floppy and said that it was all ok but when
it rebooted it came up with CMOS bad checksum press F1 to enter setup, which
I did and reset everything.

After doing a search on Google I thought maybe the battery was bad and tried
replacing that with a new one and flashed the bios again but it still comes
up with CMOS bad checksum after it restarts for the first time. If I go into
the bios and reset everything it all works ok.

The question is... is the motherboard ok and the CMOS error message error
normal after using the EZ Flash utility as I am trying to put the same bios
version on and is the short beep after the via sata driver loads normal?

Thanks for taking the time to read this and I hope someone can put my mind
at rest.

Regards,
Richard
 
"Richard&Sue" said:
Hi, I have just purchased a new PC which has the K8V SE Deluxe m/b
installed.

The problems I have had are that after only a couple of times using the
machine on the first day the bios lost its settings and I had to go in by
pressing F1 and reset the date, time etc. After which it worked ok. It does
do a short beep after it loads the via sata driver and then continues to
load Windows.

This morning when I turned it on it said that it couldn't find the via sata
drive connected, so I restarted it and all worked fine. I downloaded the
current 1001 bios and used the EZ Flash update using Ctrl + F2 when booting
thinking that maybe the bios was faulty and reprogramming it would be a good
idea! It read the data from the floppy and said that it was all ok but when
it rebooted it came up with CMOS bad checksum press F1 to enter setup, which
I did and reset everything.

After doing a search on Google I thought maybe the battery was bad and tried
replacing that with a new one and flashed the bios again but it still comes
up with CMOS bad checksum after it restarts for the first time. If I go into
the bios and reset everything it all works ok.

The question is... is the motherboard ok and the CMOS error message error
normal after using the EZ Flash utility as I am trying to put the same bios
version on and is the short beep after the via sata driver loads normal?

Thanks for taking the time to read this and I hope someone can put my mind
at rest.

Regards,
Richard
Click to expand...

There are a couple of possibilities. First I'll describe how the CMOS
works, and then you can recollect what you've done to the board, to
see if symptoms and mechanism line up. The following is a "generic"
description, as Via doesn't provide downloadable datasheets for
their chipsets like Intel does.

The Southbridge is divided into two halves, from a powering perspective.
The biggest part of it, only receives power when you push the button
on the front of the computer. That part of the chip doesn't need power
when the computer is sleeping or powered down.

The second part of the Southbridge contains a Real Time Clock circuit
and static CMOS RAM (the CMOS). The CMOS is where the settings for the
motherboard are stored. Since this kind of memory is volatile, it
needs power all the time.

Motherboard makers have two sources of power, and they are joined by
a dual diode (three legged device). One source of power is derived
from +5VSB, and as long as the computer is plugged in and the switch
on the back of the computer is in the "ON" position, current comes
from +5VSB to power the CMOS/RTC. There is no current limiting
resistor in this path - so if you do the "clear the CMOS" procedure
while the board is receiving +5VSB, the shorting jumper will draw
a lot of current through the dual diode, damaging it or the tiny
copper tracks connected to it.

The second source of power is the 3V coin cell, and usually there is
a 1K ohm resistor from the cell, to the dual diode. The resistor
limits the current, so the coin cell cannot be overloaded by clearing
the CMOS.

The reason the +5VSB path doesn't limit the current, is more current
is required to run the CMOS while the computer is running, versus
when it is sleeping.

So, the question is, have you or the people who assembled the computer,
ever "cleared the CMOS" while the computer was plugged in. If so,
that could account for flaky CMOS operation. To verify this is
the problem, a voltmeter must be connected to the point in the
circuit after the dual diode, and the voltage there has to be
between 2V and 3V, for the CMOS/RTC to remember data and keep time.
If the voltage drops below 2V or so, the clock could stop, or any
settings could be corrupted.

A second possibility, is the CMOS memory in the Southbridge is
actually bad, in which case the Southbridge would have to be replaced.
This isn't likely to be the source of the problem, as damage to
the "traditional" design of the CMOS/RTC sustaining power circuit
is way more likely to be the problem.

I tried looking at a picture of a K8V motherboard, to see if I
could identify the dual diode. I cannot see anything close to
the Southbridge that might be it. It can be damaged without
visible proof on the outside of it. The device has three legs
and has "K45" printed on it, in letters so small, that I use
a magnifying glass to read the text. There are some sample
device info sheets mentioned here:

http://groups.google.com/groups?hl=...-1&[email protected]

http://groups.google.com/[email protected]

So, if you've ever cleared the CMOS, while the green LED on the
motherboard is lit (indicating +5VSB is present), that could be
enough to damage the motherboard circuit.

HTH,
Paul
 
Paul said:
There are a couple of possibilities. First I'll describe how the CMOS
works, and then you can recollect what you've done to the board, to
see if symptoms and mechanism line up. The following is a "generic"
description, as Via doesn't provide downloadable datasheets for
their chipsets like Intel does.

The Southbridge is divided into two halves, from a powering perspective.
The biggest part of it, only receives power when you push the button
on the front of the computer. That part of the chip doesn't need power
when the computer is sleeping or powered down.

The second part of the Southbridge contains a Real Time Clock circuit
and static CMOS RAM (the CMOS). The CMOS is where the settings for the
motherboard are stored. Since this kind of memory is volatile, it
needs power all the time.

Motherboard makers have two sources of power, and they are joined by
a dual diode (three legged device). One source of power is derived
from +5VSB, and as long as the computer is plugged in and the switch
on the back of the computer is in the "ON" position, current comes
from +5VSB to power the CMOS/RTC. There is no current limiting
resistor in this path - so if you do the "clear the CMOS" procedure
while the board is receiving +5VSB, the shorting jumper will draw
a lot of current through the dual diode, damaging it or the tiny
copper tracks connected to it.

The second source of power is the 3V coin cell, and usually there is
a 1K ohm resistor from the cell, to the dual diode. The resistor
limits the current, so the coin cell cannot be overloaded by clearing
the CMOS.

The reason the +5VSB path doesn't limit the current, is more current
is required to run the CMOS while the computer is running, versus
when it is sleeping.

So, the question is, have you or the people who assembled the computer,
ever "cleared the CMOS" while the computer was plugged in. If so,
that could account for flaky CMOS operation. To verify this is
the problem, a voltmeter must be connected to the point in the
circuit after the dual diode, and the voltage there has to be
between 2V and 3V, for the CMOS/RTC to remember data and keep time.
If the voltage drops below 2V or so, the clock could stop, or any
settings could be corrupted.

A second possibility, is the CMOS memory in the Southbridge is
actually bad, in which case the Southbridge would have to be replaced.
This isn't likely to be the source of the problem, as damage to
the "traditional" design of the CMOS/RTC sustaining power circuit
is way more likely to be the problem.

I tried looking at a picture of a K8V motherboard, to see if I
could identify the dual diode. I cannot see anything close to
the Southbridge that might be it. It can be damaged without
visible proof on the outside of it. The device has three legs
and has "K45" printed on it, in letters so small, that I use
a magnifying glass to read the text. There are some sample
device info sheets mentioned here:

http://groups.google.com/groups?hl=...-1&[email protected]
http://groups.google.com/[email protected]

So, if you've ever cleared the CMOS, while the green LED on the
motherboard is lit (indicating +5VSB is present), that could be
enough to damage the motherboard circuit.

HTH,
Paul
Click to expand...

Thanks for your quick reply Paul, I have not cleared the CMOS whilst the
green LED was lit. When I changed the battery I made sure the wall socket
was powered off so no power was going to the motherboard. I do not have the
facility to check the voltage being supplied.

Apart from the first occurance of having to enter all the BIOS settings when
I first received the machine everything had been going ok, until this
morning when the Via SATA drive was not detected and I thought that flashing
the BIOS may make a difference and when that came up with the checksum error
I thought I would ask here.

I look forward to receiving any other input from yourself or anybody else
regarding this.

Regards,
Richard
 
"Richard&Sue" said:
Thanks for your quick reply Paul, I have not cleared the CMOS whilst the
green LED was lit. When I changed the battery I made sure the wall socket
was powered off so no power was going to the motherboard. I do not have the
facility to check the voltage being supplied.

Apart from the first occurance of having to enter all the BIOS settings when
I first received the machine everything had been going ok, until this
morning when the Via SATA drive was not detected and I thought that flashing
the BIOS may make a difference and when that came up with the checksum error
I thought I would ask here.

I look forward to receiving any other input from yourself or anybody else
regarding this.
Click to expand...

After flashing the BIOS, did you enter the BIOS and use
the "Load Setup Defaults" option ? That is supposed to
format the data structures according to the layout of
the new BIOS image.

Paul
 
Paul said:
After flashing the BIOS, did you enter the BIOS and use
the "Load Setup Defaults" option ? That is supposed to
format the data structures according to the layout of
the new BIOS image.

Paul
Click to expand...

What I did was flash the BIOS and then it rebooted by itself and I just let
it run. Should I have entered the BIOS by pressing the delete key as soon as
it rebooted and loaded the setup defaults then?

Richard
 
"Richard&Sue" said:
What I did was flash the BIOS and then it rebooted by itself and I just let
it run. Should I have entered the BIOS by pressing the delete key as soon as
it rebooted and loaded the setup defaults then?

Richard
Click to expand...

"Load Setup Defaults" is mentioned in some of the other Asus
manuals. You can even try it now, if you like. Generally, I
like to write down any settings that were customized, before
flashing the BIOS, as after doing a "Load Setup Defaults",
you'll need to set customized stuff up again. (There is an
old utility that is claimed to save the contents of the
BIOS setup screens, but I don't know if it works any more
or not - called cmos.exe)

As for the drive, it was working OK at one point ? I wouldn't
expect flashing the BIOS would bring it back, if it suddenly
disappeared. Have you added any other hardware lately ?
Maybe there is a conflict somewhere with some new hardware.

Does the drive make any funny sounds at startup ? Like it
is trying over and over again to find track zero ?

Paul
 
Richard&Sue said:
Hi, I have just purchased a new PC which has the K8V SE Deluxe m/b
installed.

The problems I have had are that after only a couple of times using the
machine on the first day the bios lost its settings and I had to go in by
pressing F1 and reset the date, time etc. After which it worked ok. It
does do a short beep after it loads the via sata driver and then continues
to load Windows.

This morning when I turned it on it said that it couldn't find the via
sata drive connected, so I restarted it and all worked fine. I downloaded
the current 1001 bios and used the EZ Flash update using Ctrl + F2 when
booting thinking that maybe the bios was faulty and reprogramming it would
be a good idea! It read the data from the floppy and said that it was all
ok but when it rebooted it came up with CMOS bad checksum press F1 to
enter setup, which I did and reset everything.

After doing a search on Google I thought maybe the battery was bad and
tried replacing that with a new one and flashed the bios again but it
still comes up with CMOS bad checksum after it restarts for the first
time. If I go into the bios and reset everything it all works ok.

The question is... is the motherboard ok and the CMOS error message error
normal after using the EZ Flash utility as I am trying to put the same
bios version on and is the short beep after the via sata driver loads
normal?

Thanks for taking the time to read this and I hope someone can put my mind
at rest.

Regards,
Richard
Click to expand...

I have had the same problem with the same motherboard, my problem was the
kingston memory I used.
Run a good memory check program, I think you will find the problem.

Ronald
 
Back
Top