CMOS auto reset

This is an old situation i just had..

I was just online when my mum plugged the vacuum cleaner in and the power went off and the computer also went off.

I turned the computer back on and it got to the "POST" where the memory test is on start up and it said "CMOS ERROR" and it proceeded to boot to windows fine.

So i rebooted and i could not see any problem apart from the cmos has been reset and the bios settings have been set back to factory default and i can no longer see the "CMOS ERROR" error message on the POST.

P.S I have a power surge protector so when the power usually goes out it does not harm my system and scan disk on windows does not run looking for errors on start up.

So my question is what is this "CMOS ERROR" that was displayed on the first boot up after the power went out and why has the cmos battery been reset just because the power went out?.

This seems like an odd situation to me can anybody shed some light on the matter?.

Thank You

What version of windows are you running?

Try THIS link for info

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Originally posted here by The Texan
What version of windows are you running?

Try THIS link for info

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Thanks for the quick response..

I am running Windows XP HE and Phoenix bios 6.0

I would not worry too much mate, but I would replace your CMOS battery, it sounds as if it is marginal right now.

That would explain the reset to "default"

;)

The power failure caused a CMOS reset, putting all important System settings to the prime or original state because it probably generated some problem with the Hardware Devices or some Drivers.

I had the CMOS Error message once when i (badly :rolleyes: ) overclocked and had my processor running with an incorrect multiplier, that may have been the case when it rolled back to factory settings, thus giving you the erro.

cheers

Sm0kinP0t is correct about why, and Nihil might be right about your battery.

What happened is what's called a "brownout" and right after that (almost immediately) a "power out" condition.

This caused the CMOS contents to either reset back to default or corrupt it sufficiently so the next reboot caused the CMOS to show the CMOS error message you saw. My money is on the latter idea.

Once the machine rebooted though, you are back in business, *kinda*.
I would reenter the CMOS settings and set the options what they were (if you had changed them in the past).

You will find your CMOS designated boot order out of sequence and some video RAM sharing back ON.
I would turn OFF all memory sharing (Video RAM, Shadow RAM) if you are using XP.

If your computer is 3 years old or older you might have a low voltage CMOS battery and not know it.
Most times, though, a low CMOS battery will show a message on bootup (as CMOS settings returns to a default state) and/or you will find your Windows clock either not on time after a reboot or missing so many seconds/minutes.
Be advised though, without an external timesource the computer is not good at keeping time and loses a minute or more over a varying time period.
I've seen low CMOS batteries lose more than a couple minutes a month, if not more AND bad CMOS batteries cause a bootup message every time.

A power strip cannot protect you from the damage a brownout can cause. Brownouts cause more damage to a computer than a total blackout.
Either way, brownout or blackout, regardless what the computer does, you need to run a scandisk on C: drive and any other hard drive partition.

The reason the computer did not run a scandisk is because the dirty flag was not set.
So, despite the lack of warning, run that scandisk every time this happens.

Last note: If you are running XP, not running a dual boot and have no other reasons not to (like your MOM would kill you, or you don't own the computer), you should convert your file format from FAT32 to NTFS.

NTFS is much more forgiving about file interruptions and damage as it is a journaling file system. Basically, it keeps track of what should be written and where it should be written prior to actually writing it, among other things. It's kinda like a check and balance system.

You will NOT lose data by a successful conversion to NTFS.
To change a FAT32 partition to an NTFS system in XP, go to START, RUN, type CMD, hit enter, type "convert c: /FS:NTFS" (type everything between the quotes but not the quotes)

A message will appear asking if you want to convert now, choose N (NO), it will then ask you if you want to schedule the convert later, choose Y (YES), then type exit, hit enter, reboot the system and while it reboots the file system will convert.
If you are going to do this, do it when you think there will be no power outages (not when your MOM is cooking or cleaning).

Once you change from FAT32 to NTFS, there is no default tool to return to FAT32. Only special software can do that.

Edit: Why do I keep saying Scandisk? I mean Checkdisk. Sheesh.

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Originally posted here by YoungNobody
I am running Windows XP HE and Phoenix bios 6.0

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Windows XP HE??

Is that the very rare High Efficiency version I've only heard about?

;)

no it stands for Hellish Equipment :)

Good response ZT3000,

I did a google search before i posted and it looks like the CMOS battery become corrupt and has re-installed to factory default so everything will proberly be fine but i was just worried if there was a possibility that the corruption had caused permeant damage.

But what is memory sharing and why do you advise me to turn it off?.

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Originally posted here by ZT3000
Windows XP HE??

Is that the very rare High Efficiency version I've only heard about?

;)

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I have always thaught of it to stand for: "Home Edition"

But seeing as it cost so much im guessing it must stand for: "High Efficiency" :P

Hideously Expensive!

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Originally posted here by YoungNobody
[B]Good response ZT3000,

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Thanks.

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But what is memory sharing and why do you advise me to turn it off?.

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Nowadays, a better term is shadowing, as lots of BIOS contain PCI slot sharing options and PCI slot options are something we don't want to change.

Look for and turn off VGA shadowing, Shadow RAM, stuff that reads like that. There will probably at most be 2 entries like this in your CMOS options.

Reason to turn them off is: These options tell the BIOS to play parlour tricks with RAM caching and RAM swapping as it pertains to stored VGA memory and upper memory filing/storing (above 640K and below 1024K). Memory manipulation using BIOS routines are notoriously slow and were once useful for slow video cards with very low onboard memory and also useful for switching stored code in and out of certain memory spots.

The computers of today do not need any of these old tricks and, in my experience and opinion, cause more problems.

Know that a computers BIOS routines are only useful on initial OS install and when a computer first boots up, if using XP. XP has it's own code in replacement of hardware BIOS and doesn't use the BIOS again. (although I believe there is an exception, right now I can't remember what it was.)

Heh..it's only 18 years of PC computer troubleshooting/repair experience talking.
Gawd, I'm getting old.

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You must spread your AntiPoints around before giving it to ZT3000 again.

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A power strip cannot protect you from the damage a brownout can cause. Brownouts cause more damage to a computer than a total blackout.
Either way, brownout or blackout, regardless what the computer does, you need to run a scandisk on C: drive and any other hard drive partition.

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I am continually pissed at how media and sales people sprog of the need and importance of SUrge Protection.. Most of the products are sugar pills.. (the only Surge protector that has ever worked for me was Durex).

Most Surge Protectors are no more trhan a MOV, that offers some over voltage protection, usually handy to reduce Spikes and (by blowing a Fuse) prevent damage from Voltage rises.
These devices offer next to no protection from Lightning stike.. (bit like a 20lb hammer to a grape). Many of these devices offer no inline filtering, and if they do it is so poorly designed it may as well not be there. These cant provide protection to power drops, or droops (brown-out), nor are they able to prevent noise getting through.
In the case of a Inductive load connecting or disconnecting (equipment motor), this situation creates a combination of Noise, transient spikes and a droops. The Noise and Droop will have been the likey contributer to your situation.. the CMOS Battery could be getting ill, but the design of the Backup circuit could allow a the noise to cause a reset of the CMOS.
The design of Computer PSU's, while allowing a wide range of input voltages, in some cases perfect regulation from supply input of 90V AC to 260V AC..BUT will allow a transient spike and Noise through without hesitation.
The only 100% reliable method of preventing this situation is a run the computer from an inverter supplied by a bank of batteries..
and as for the $9.99 surge protector.. you know these are only good for one surge..?.. many, even those with the OK lamp, are non functional after the first belt....