Bios resets when power removed even with new battery

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Doc

Is there any reason the bios would keep resetting when power is removed,
even though it has a new battery, other than some problem with the physical
connection between the battery and the CMOS?
 
Doc said:
Is there any reason the bios would keep resetting when power is removed,
even though it has a new battery, other than some problem with the physical
connection between the battery and the CMOS?
Click to expand...

Are you sure the ccmos (clear CMOS) jumper is properly placed
on the motherboard (either not there at all, or placed on the correct
set of jumpers, depending on motherboard)?
 
"Doc" said:
Is there any reason the bios would keep resetting when power is removed,
even though it has a new battery, other than some problem with the physical
connection between the battery and the CMOS?
Click to expand...

If you do a "clear CMOS" operation, without removing all power
by unplugging the computer, it is possible to damage the power
"ORing" diodes that feed the CMOS well on the Southbridge.
A couple of people have repaired damage like that, by installing
a couple of new switching diodes. (The component below is a
dual diode, where two diodes are packaged in one three-legged
package. Some people have used two single diodes, and done
some hairy soldering, to replace the busted function.)

An example of the damaged component is here - BAS40W-05.
The top of the component has the letters "K45" in print so
tiny, you need a magnifying glass to read it. (I have three
motherboards here, with a K45 component on them. K45 is three
of the characters in the part number, and there are usually
a couple other smaller random digits written on the top of the
component as well.) Look for a three-legged black device
near the CMOS battery. (Yes, it is hard to find. But an
obvious one, if you find a three legged tiny device that is
burned on top.)

http://www.diodes.com/tracker/pdftr...com/product_catalog/search.php&ds=ds30114.pdf

HTH,
Paul
 
Doc said:
Is there any reason the bios would keep resetting when power is removed,
even though it has a new battery, other than some problem with the physical
connection between the battery and the CMOS?
Click to expand...

Failed bios upgrade or corruption due to (rare) viruses or other random
factors (also very rare). In which case, try to re-flash if you can.

Cmos clear jumper set in the wrong spot. I did see a case where the
metal part of the jumper separted from the plastic part, so when the
jumper was removed, the metal part was still shorting the connection.

Bad bios chip. Which probably means you're screwed.

CMOS settings you tried caused a hang on boot, and settings were
automatically reverted to default.
 
Doc said:
Is there any reason the bios would keep resetting when power is removed,
even though it has a new battery, other than some problem with the physical
connection between the battery and the CMOS?
Click to expand...

Failed bios upgrade or corruption due to (rare) viruses or other random
factors (also very rare). In which case, try to re-flash if you can.

Cmos clear jumper set in the wrong spot. I did see a case where the
metal part of the jumper separted from the plastic part, so when the
jumper was removed, the metal part was still shorting the connection.

Bad bios chip. Which probably means you're screwed.

CMOS settings you tried caused a hang on boot, and settings were
automatically reverted to default.
 
Doc said:
Is there any reason the bios would keep resetting when power is removed,
even though it has a new battery, other than some problem with the physical
connection between the battery and the CMOS?
Click to expand...

1. The new battery may be bad.
2. You bent the clip too far upwards when you installed the new battery,
depending on the mobo.
3. The bios circuit went bad on the motherboard which is sometimes
solved by using an external bios battery.
 
are you resetting and then loading defaults(or whatever you wish) then
saving or are you going from short to booting to the desktop?
 
Doc said:
Is there any reason the bios would keep resetting when power is removed,
even though it has a new battery, other than some problem with the
physical
connection between the battery and the CMOS?
Click to expand...


Have you tested the new battery? I've bought new ones which were DOA.
 
The battery is not in upside down is it ?
( I must admit I did that once with a button type battery)
Or perhaps it's corrupt and you're not holding the button down long
enough to flush it ? So still corrupt ? For Deskpro's - to reset the
CMOS : press the CMOS button and HOLD it depressed for 5+ seconds.
Let us know if it works.

Bobb
 
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