cmos checksum error

[Amanda]

Hello,

Each time I boot my computer, it shows cmos checksum error. Press F8 for
system configuration but the F8 doesn't work, F9 doesn't work either. F1
allows it to boot and the system gets set at 1st Jan 2007 12.00 am.

Regardless of how many times I change the bios, it will revert after each
power down. I don't have a floppy but it seems to insist i do, strange thing
is .. a floppy disk drive and floppy controller exist on my device manager.
If I remove it, the computer detects the zoombie floppy and reinstalls it.

I've also replaced the button battery but that didn't help.

Could anyone help?

Thanks in advance.
Sonny

P.S I had to reset the time before posting because it says this post is too
old

 

[Unknown]

How did you change the BIOS? Did you rewrite it?

 

[Bob I]

You have a hardware problem. Are you sure the button battery was good?
Are you killing power to the PC externally, like with a power strip? If
so, don't.

 

[Ben Myers]

Hello,
Each time I boot my computer, it shows cmos checksum error. Press F8 for
system configuration but the F8 doesn't work, F9 doesn't work either. F1
allows it to boot and the system gets set at 1st Jan 2007 12.00 am.

<snip>

Try tapping the F8 key repeatedly or hitting it before the error message is
displayed. Be sure to save any changes you make. If this doesn't help, try
a different keyboard.

Ben

 

[Paul]

Hello,

Each time I boot my computer, it shows cmos checksum error. Press F8 for
system configuration but the F8 doesn't work, F9 doesn't work either. F1
allows it to boot and the system gets set at 1st Jan 2007 12.00 am.

Regardless of how many times I change the bios, it will revert after each
power down. I don't have a floppy but it seems to insist i do, strange thing
is .. a floppy disk drive and floppy controller exist on my device manager.
If I remove it, the computer detects the zoombie floppy and reinstalls it.

I've also replaced the button battery but that didn't help.

Could anyone help?

Thanks in advance.
Sonny

P.S I had to reset the time before posting because it says this post is too
old

Other possible reasons:

1) The new battery is already flat. Some retailers carry old stock.

2) The motherboard has a defect in the battery area, which is
rapidly draining the battery.

3) The "Clear CMOS" jumper is in the wrong position.

4) The "Clear CMOS" jumper was used, while the motherboard still
had power. A tiny diode has been damaged by doing so, such as the
BAS40W-05. The dual diode, with common cathode, is in the
CMOS battery path, and logical ORs together the motherboard
3VSB power source, with the CMOS battery power source. If the
diode package is damaged, that can lead to CMOS problems. Three
of my motherboards, use this particular device. One poster here,
repaired his by using two separate 1N914 type diodes, and claims it
works fine that way. So he replaced the three-legged dual diode,
with two separate diodes. One reason the BAS40W-05 in this example
is used, is because of low Vf forward voltage drop. The diode also
prevents the CR2032 coin cell battery from being charged. You
cannot safely charge a CR2032.

http://www.diodes.com/datasheets/ds30114.pdf

When "Clearing CMOS", you should always unplug the computer, because
so many motherboards have this potential fault mode in their design.

The odds of being able to find that component, are pretty low.
Logically, it should be located near the battery, but there is
no reason it cannot be placed all the way on the other side
of the motherboard. If the motherboard designer is a meany, you might
never find it. It is so small, and so similar to many other three-legged
devices, you could spend hours staring at the motherboard looking for
it. I've spent up to 2 hours with a stereoscopic microscope in the
lab, looking for components of that type. That is how long it takes to
do a thorough search. You need some magnification, to be able to read
the "K45" printed on top of that example component. At home, I use
a small magnifying glass for that purpose.

If you've never used the "Clear CMOS" jumper on your motherboard,
then you have nothing to worry about. But if you frequently use
that function, then you might have inadvertently left the power
on the system.

HTH,
Paul

 

[Amanda]

Hi,

Thanks to all who replied. I reset the BIOS hitting delete, change the first
boot sequence to hard disk, disable the search for floppy. Change the time
yet again.

Bob L, I bought a brand new battery and its the same thing.

regards
Sonny

Hello,
Each time I boot my computer, it shows cmos checksum error. Press F8 for
system configuration but the F8 doesn't work, F9 doesn't work either. F1
allows it to boot and the system gets set at 1st Jan 2007 12.00 am.

<snip>

Try tapping the F8 key repeatedly or hitting it before the error message is
displayed. Be sure to save any changes you make. If this doesn't help, try
a different keyboard.

Ben

 

[Amanda]

Ben,

I've just rebooted and tried hitting the F8 button, doesn't work, comes up
to the same screen with the f8 f9 f1 and delete option.

regards,
Sonny

Hello,
Each time I boot my computer, it shows cmos checksum error. Press F8 for
system configuration but the F8 doesn't work, F9 doesn't work either. F1
allows it to boot and the system gets set at 1st Jan 2007 12.00 am.

<snip>

Try tapping the F8 key repeatedly or hitting it before the error message is
displayed. Be sure to save any changes you make. If this doesn't help, try
a different keyboard.

Ben

 

[Amanda]

Bob,

Nope it didn't work. Its the same even if i do a Start-Turn off
Computer-Restart.

Sonny

 

[Bob I]

If it won't hold the BIOS settings through a simple Restart, (never
actually removes power from the motherboard)then it certainly is a
hardware issue with the motherboard.

 

[Jim]

Bob,

Nope it didn't work. Its the same even if i do a Start-Turn off
Computer-Restart.

Sonny

Have you done a virus scan ?

 

[Unknown]

You need to rewrite the BIOS. Contact the computer manufacturer and get the
correct method to rewrite the BIOS.
I use the floppy to update or rewrite the BIOS.

 

[Ben Myers]

Ben,
I've just rebooted and tried hitting the F8 button, doesn't work, comes up
to the same screen with the f8 f9 f1 and delete option.

If you are saying that pressing the F8 key does nothing when the message
is displayed, try a different keyboard. If you are getting into the BIOS setup,
make sure you are saving the changes, since this typically is not done automatically.

Ben

 

[Linus]

After you replace the CMOS battery, you often need to reset the CMOS. Usually
you do this by taking the battery out, installing it backwards in its holder
for 20 or 30 minutes to bleed off all the current. Then just take the battery
out, turn it around and install it properly.

Some mother boards have shorting terminals near the battery that let you
bleed off the current without removing the battery, check your users guide
for instructions on how to use those.

Either way you do it, when you restart your computer, the OS will reload the
CMOS with clean settings that may solve your problem.

Linusverl

 

[Amanda]

Thanks to all who replied.

Ben - Just bought a new keyboard and tried, nope f8 & f9 still doesn't work.
Only working options are f1 and delete. Yes, i did save after changing the
bios setup. Doesn't work.

Jim - Yes I have anti virus installed and schedule to update and run
everyday. But the time set back because of the checksum error has made it
run at rather untimely. I do check the history once in a while to make
sure.

Linus - "After you replace the CMOS battery, you often need to reset the
CMOS. Usually you do this by taking the battery out, installing it backwards
in its holder" I don't quite understand this, do I take reset after I take
out the battery or after I replaced the battery? I hope you mean to take out
the old battery, drain off with the old battery and then replace with new.
Is that it? I'll try that.

I seem to think that the motherboard is dying. Either I get a new one or I
just punch F1 each time I turn on the computer and ignore the time.

Regards
Sonny

 

[Jose]

Thanks to all who replied.

Ben - Just bought a new keyboard and tried, nope f8 & f9 still doesn't work.
Only working options are f1 and delete. Yes, i did save after changing the
bios setup. Doesn't work.

Jim - Yes I have anti virus installed and schedule to update and run
everyday. But the time set back because of the checksum error has made it
run at rather untimely.  I do check the history once in a while to make
sure.

Linus - "After you replace the CMOS battery, you often need to reset the
CMOS. Usually you do this by taking the battery out, installing it backwards
in its holder" I don't quite understand this, do I take reset after I take
out the battery or after I replaced the battery? I hope you mean to take out
the old battery, drain off with the old battery and then replace with new..
Is that it? I'll try that.

I seem to think that the motherboard is dying. Either I get a new one or I
just punch F1 each time I turn on the computer and ignore the time.

Regards
Sonny

I don't see where you have identified your system well enough (the
right questions have not been asked).

You can try things all day long - how it that working out?

If your system boots, do this and we can identify the motherboard and
then you might get some better ideas:

Please provide additional information about your system:

Click Start, Run and in the box enter:

msinfo32

Click OK, and when the System Summary info appears, click Edit, Select
All, Copy and then paste the information back here.

There will be some personal information (like System Name and User
Name), and whatever appears to be private information to you, just
delete it from the pasted information.

This will minimize back and forth Q&A and eliminate guesswork. (too
late for the guesswork part).

 

[Jose]

After you replace the CMOS battery, you often need to reset the CMOS. Usually
you do this by taking the battery out, installing it backwards in its holder
for 20 or 30 minutes to bleed off all the current. Then just take the battery
out, turn it around and install it properly.

Some mother boards have shorting terminals near the battery that let you
bleed off the current without removing the battery, check your users guide
for instructions on how to use those.

Either way you do it, when you restart your computer, the OS will reload the
CMOS with clean settings that may solve your problem.

Linusverl

Where can I read about this method of resetting the CMOS by inserting
the battery backwards for 20 to 30 minutes to bleed off the current?

 

[Unknown]

You can't read about putting the battery in backwards because it doesn't
exist. That is
about the dumbest thing you can do on anything with a battery.

After you replace the CMOS battery, you often need to reset the CMOS.
Usually
you do this by taking the battery out, installing it backwards in its
holder
for 20 or 30 minutes to bleed off all the current. Then just take the
battery
out, turn it around and install it properly.

Some mother boards have shorting terminals near the battery that let you
bleed off the current without removing the battery, check your users guide
for instructions on how to use those.

Either way you do it, when you restart your computer, the OS will reload
the
CMOS with clean settings that may solve your problem.

Linusverl

Where can I read about this method of resetting the CMOS by inserting
the battery backwards for 20 to 30 minutes to bleed off the current?

 

[Paul]

Unknown wrote:
You can't read about putting the battery in backwards because it doesn't
exist. That is about the dumbest thing you can do on anything with a battery.

There is a diode in that path, that also functions as
reverse polarity protection. Go to page 18 of this document, and
look at diode D3 in the bottom left hand corner of page 18. if
the battery were reversed, the D3 diode would be reverse biased,
and the current could not flow.

http://www.intel.com/design/chipsets/designex/BXDPDG10.htm

Also, as a result of that diode, plopping the battery in
backwards, isn't that effective. The provided CMOS jumper,
applied to the three pin header shown in that schematic, is
effective at doing its job. It won't take long to
drain the CMOS well. It's a bit harder, on the motherboards
that provide solder pads and no header pins, to consistently
hold the connection long enough, to complete
the draining. But if you have a header to work with,
that is just as good at sitting in a holding pattern, as
jamming the battery in backwards.

Paul

 

[Amanda]

Where can I read about this method of resetting the CMOS by inserting
the battery backwards for 20 to 30 minutes to bleed off the current?

I'm not sure about that either, you'll have to check with Linus, just a few
threads up.

 

[Amanda]

Jose,

Here's what you requested.

OS Name Microsoft Windows XP Home Edition
Version 5.1.2600 Service Pack 2 Build 2600
OS Manufacturer Microsoft Corporation
System Name PAPA
System Manufacturer Biostar
System Model 945GC Micro 775
System Type X86-based PC
Processor x86 Family 6 Model 15 Stepping 13 GenuineIntel ~1996 Mhz
Processor x86 Family 6 Model 15 Stepping 13 GenuineIntel ~1996 Mhz
BIOS Version/Date Phoenix Technologies, LTD 6.00 PG, 5/23/2007
SMBIOS Version 2.4
Windows Directory C:\WINDOWS
System Directory C:\WINDOWS\system32
Boot Device \Device\HarddiskVolume1
Locale United States
Hardware Abstraction Layer Version = "5.1.2600.2180
(xpsp_sp2_rtm.040803-2158)"
User Name PAPA\papa
Time Zone Malay Peninsula Standard Time
Total Physical Memory 1,024.00 MB
Available Physical Memory 591.12 MB
Total Virtual Memory 2.00 GB
Available Virtual Memory 1.96 GB
Page File Space 2.39 GB
Page File C:\pagefile.sys

Thanks to all who replied.

Ben - Just bought a new keyboard and tried, nope f8 & f9 still doesn't
work.
Only working options are f1 and delete. Yes, i did save after changing the
bios setup. Doesn't work.

Jim - Yes I have anti virus installed and schedule to update and run
everyday. But the time set back because of the checksum error has made it
run at rather untimely. I do check the history once in a while to make
sure.

Linus - "After you replace the CMOS battery, you often need to reset the
CMOS. Usually you do this by taking the battery out, installing it
backwards
in its holder" I don't quite understand this, do I take reset after I take
out the battery or after I replaced the battery? I hope you mean to take
out
the old battery, drain off with the old battery and then replace with new.
Is that it? I'll try that.

I seem to think that the motherboard is dying. Either I get a new one or I
just punch F1 each time I turn on the computer and ignore the time.

Regards
Sonny

I don't see where you have identified your system well enough (the
right questions have not been asked).

You can try things all day long - how it that working out?

If your system boots, do this and we can identify the motherboard and
then you might get some better ideas:

Please provide additional information about your system:

Click Start, Run and in the box enter:

msinfo32

Click OK, and when the System Summary info appears, click Edit, Select
All, Copy and then paste the information back here.

There will be some personal information (like System Name and User
Name), and whatever appears to be private information to you, just
delete it from the pasted information.

This will minimize back and forth Q&A and eliminate guesswork. (too
late for the guesswork part).