What does it mean when unplugging the computer makes it forget the bios date?

[mouser]

After a recent battle with the computer i got it back together and working, but one thing has never been the same since:
When i remove power to the PC, and then turn it back on, the bios forgets the date and time.

Does it mean the motherboard battery is dead? or that i messed it up somehow?  seems odd timing.

[Eóin]

Dead, or maybe just loose but I would say yes the battery is most likely the issue.

[cranioscopical]

When i remove power to the PC, and then turn it back on, the bios forgets the date and time.

-mouser (December 24, 2008, 02:21 PM)

You haven't one of those new-fangled mobo's with the Mouser BIOS do you?
They're the kind that initiate the boot process and then fade away for a while.

[steeladept]

Yes, typically that means a dead battery - though I suppose Chris could be right too.

[Carol Haynes]

If you swap the battery and it still doesn't work have a look at the battery socket connections on the mobo - I recently had to fix a laptop computer by resoldering the mobo links to the CMOS battery holder. Works fine now. The joints can get damaged/cracked removing a battery or you may have a dry joint.

Definitely sounds like a battery issue though.

[40hz]

I'm gonna say: A - Battery...
Final answer, Meredith!

[mouser]

Thanks for all the advice.
Unfortunately, after replacing the battery problem remains. Strange.

[wr975]

After a recent battle with the computer i got it back together and working...

-mouser (December 24, 2008, 02:21 PM)

Messed around with some jumpers? Perhaps the bios reset jumper is set? (But then the computer wouldn't boot, or?)

[40hz]

Very bizarre. Especially in absence of any damage to the battery holder.

Is there any debris or other thing shorting on/against the mobo? If you removed the mobo, check to see if there's anything caught under the board and that all grounding screws are installed. Chance you might have a hairline crack somewhere on the board that is preventing the battery current from getting to the clock. Check to see if board is flexed or screwed down too tightly.

Also scan for damaged/nicked traces on board. Try gently reseating all socketed chips by giving each one a gentle push after disconnecting the power cord.

Long shot - try reflashing your BIOS.

[Carol Haynes]

Did you reset the CMOS completely when you replaced the battery?

Usually -

• switch off and unplug
• take out the battery
• move the CMOS link to clear position
• wait 5 minutes
• move CMOS link back to normal position
• replace battery
• plugin and switch on
• Enter BIOS and restore default settings

I have found this sequence necessary on more than one system because a failing CMOS battery leaves the BIOS settings and NVRAM in an inconsistent state - though not necessarily bad enough for the BIOS to report an error.

[mouser]

all if this started when i flashed the bios a couple months ago and totally incapacitated the machine, which could only be recovered by doing a crazy hotflash of the bios back to old version.

so i'm very hesitant to muck around with things too much more.

[4wd]

all if this started when i flashed the bios a couple months ago and totally incapacitated the machine, which could only be recovered by doing a crazy hotflash of the bios back to old version.

so i'm very hesitant to muck around with things too much more.

-mouser (December 26, 2008, 05:21 PM)

Hotflashing - I bet that was fun

If it were me, (and based on the new info of having been hotflashed), test after each step stopping when/if it works:

1) First try the obvious as Carol has said, total reset of the BIOS settings.  I'd add going into it on first boot and reset to Safe Defaults to see if the clock fires up.
2) Reflash the BIOS from DOS - boot from a DOS 6/7 floppy or flash drive and do it the old fashioned way from the CLI.  Just a mention here, you really should always flash the BIOS from DOS - there's just too many things going on in Windows to consider flashing reliably.
3) Remove the BIOS chip and then carefully reseat it back in again - this will wipe the contacts/pins and might clean up any suspect connection between the two - maybe it's not fully seated from it's previous removal.
4) If you had the equipment, (not many people do), I'd also consider removing the BIOS chip and programming using an (E)PROM/Flash programmer.

What was the motherboard?

[Carol Haynes]

It is an interesting topic flashing BIOSes. Almost all manufacturers now provide 'Live' windows based flash utilities but if you read the small print they all say you shouldn't use them.

A few years ago (when I was more into hardware stuff) I used to be a regular(prolific) poster on MSI forums (don't look for me there now as they started their forums again from scratch). One of the official notifications on the MSI forums was NEVER use Live Flash utilities (even those provided by MSI with their motherboards).

If a problem appeared after a BIOS flash I suspect that is the root cause of the issue. Reflash your BIOS from a floppy with the DOS utility from the manufacturer. If it has the option to clear all settings and clear NVRAM also use those command line switches.

As a rule of thumb I always download or backup the version of the BIOS that was originally supplied by the motherboard and most mobo manufacturers have a failsafe method of restoring a BIOS from a floppy disc if the burn should fail. In the case of MSI it is a key combination on power on and you need a floppy disc with just the BIOS with a fixed name and extension. Not sure about other manufacturers methods but research them before doing any ROM flashes and making an appropriate failsafe recovery is essential before you do anything else.

[mouser]

Well i'll you what a really smart thing to do would be.. and something i just keep meaning to do is:
there are places that will actually send you a replacement bios chip for your PC, already flashed for latest version, for like $20 or $30.

after seeing how badly my system got messed up after latest failed flashing attempt -- and only being able to recover it by luck, i think it would be really smart for everyone to order a spare pre-flashed bios chip for their pc ahead of time, for use in emergencies.

[Carol Haynes]

Don't forget the chip extraction and insertion tool too !

[4wd]

after seeing how badly my system got messed up after latest failed flashing attempt -- and only being able to recover it by luck, i think it would be really smart for everyone to order a spare pre-flashed bios chip for their pc ahead of time, for use in emergencies.

-mouser (December 26, 2008, 08:07 PM)

Or buy a motherboard that has a dual BIOS, ie. Gigabyte.  You can only update one, the other remains at the factory supplied version for recovery after a bad flash or other accident.

[y0himba]

The computer has Alzheimer's?