Weak CMOS Battery May Prevent Your Computer from Booting!

[Fly Guy]

For the last two years I couldn't figure out why my three year old computer wouldn't boot. It wouldn't turn on after a power outage. And even if I did properly shut down the computer the night before, it still wouldn't turn on the next morning. I would have to drain the computer by disconnecting the PSU. At first it was a few minutes, then it gradually took a whole day for the computer to drain, then only would the computer boot up. What confused me was the computer worked like a champ when the computer decided to power on.

Then just last week my computer acted even more strange than what I've described above. The computer would power up after pressing the power button but then it would immediately shut down after two seconds. I looked online and the comments were mostly, "The culprit is most likely the PSU. You need to test your computer with another PSU."

Another person with similar computer issues like me jumped through loops with the advice they gave him online, e.g. re-seat hardware, install another PSU, etc. None worked so he decided to change CMOS battery. The computer then worked like a champ again and has no problem booting. And so did this too work for me. No costly unnecessry PSU, CPU, RAM, MOBO replacement.

Anyone has any theories as to why a weak CMOS battery would prevent the computer from booting and shutting down mid way before a complete boot? It's ridiculous. You will not find this advice on the web that the CMOS battery could be the culprit because as they explain, "The purpose of the CMOS battery is to only hold date and time. A dead or weak CMOS battery will not prevent the computer from booting. You'll just lose date and time."

[The Giving One]

To those that think the power button (therefore the case) is the issue, can you not bench boot the board while it is still in the case by disconnecting the connectors to the power and reset pins and jump the pins with a small tool and therefore eliminate the power button as the issue ?

That way, the battery is still left in the realm of possibilities and the power button is taken out. Just an idea....

[viperwolf02]

Originally posted by The Giving One:

To those that think the power button (therefore the case) is the issue, can you not bench boot the board while it is still in the case by disconnecting the connectors to the power and reset pins and jump the pins with a small tool and therefore eliminate the power button as the issue ?

That way, the battery is still left in the realm of possibilities and the power button is taken out. Just an idea....

on my board it has a start button and reset button. I eliminated the possiability of it being my trooper case. I also tried the pins with same results. I understand though, we all have the same symptoms but it could be different problems.

[The Giving One]

Originally posted by _I_:

ahci might cause that if the cmos battery is low and it resets without telling the os that bios settings were changed
windows wont boot with non approved bios changes

This is an excellent point and good thinking here by the "mystery man".

I suggest that if you can, boot into your BIOS and check the settings there. From what I understand, default BIOS settings should be implemented in the case of a removed or dead battery so this makes much sense to me.

Check your BIOS settings.

[viperwolf02]

it could be, I run mine in AHCI. My battery tested at 3.05v. Is that to low for a cmos battery?

[[☥] - CJ -]

Originally posted by The Giving One:

To those that think the power button (therefore the case) is the issue, can you not bench boot the board while it is still in the case by disconnecting the connectors to the power and reset pins and jump the pins with a small tool and therefore eliminate the power button as the issue ?

That way, the battery is still left in the realm of possibilities and the power button is taken out. Just an idea....

i would but i dont have the tools to do so

[viperwolf02]

So the last 4 start ups ive tried. I did not have to remove the cmos battery. just kill all power and let it sit for 10-15 mins, and it starts up and runs great. any ideas now?

[[☥] - CJ -]

Originally posted by viperwolf02:

So the last 4 start ups ive tried. I did not have to remove the cmos battery. just kill all power and let it sit for 10-15 mins, and it starts up and runs great. any ideas now?

I had issues like that at one point with an old 775 system, turns out one of the DIMM slots was causing it when a RAM stick was placed into it.

[The Giving One]

Originally posted by viperwolf02:

it could be, I run mine in AHCI. My battery tested at 3.05v. Is that to low for a cmos battery?

That seems pretty good to me. According to the good BadMotha, that should be ok.

http://steamcommunity.com/discussions/forum/11/618460171318429760/?ctp=2#c360670708778783096

Originally posted by ☥ - CJ -:

i would but i dont have the tools to do so

You really don't need any special tools, just a small blunt metal object like a little screwdrive or whatnot (insulated so you can hold it) and you just jump the two pins that normally hook to the power button. Then, the board should post with just RAM and CPU and CPU cooler, but if you do it in the case of course, you might have other hardware hooked up.

https://www.youtube.com/watch?v=FuPZlliGqBw

[Bad 💀 Motha]

CR2032 are 3V; so right around that 3volt area/reading and it should be a fine/working battery. If it drops to around 2.9V and under, than it is failing, going bad.

[viperwolf02]

Thanks for the heads up guys. well i went to the tech today and was confused also. I explained to him what happened with my dimm slots. He just said, yeah that happens sometimes. and then showed him the problem. all i could think while we were talking and he was looking at it was, i did that, i did that also, yep i tried that, i did that already, already tried, did that already, and so on.

Im just going to assume bc im not a tech, that somehwere on the board is some type of protective capacitor or something. If you turn the power on after shuting down, the circuit is still loaded and wih thte push of the PSU. It kiks out thinking its a power surge. So if you allow the circuit to bleed out, it has a fresh start. I feel as though that would be in the PSU? although it checked good.

My answer to this problem, well i dont have one. I just have to keep in mind that if i shut it down, it will need time or just kill the power altogether. Im not ready to dish out the money for another build right now. I can run every game maxed out and it just purs. So if you have the same problem and cannot return. Just make sure your cmos battery is good so you dont lose bios settings. Then you can just kill the power for 10 mins or let it sit for a few hours wih the power still plugged.

[Bad 💀 Motha]

If you want to flush the Motherboard power fully; power off the system, disconnect the PSU (or turn off the main PSU switch on the back) and then press the Case power button. This is only when power cycles are close enough to one another, which you should avoid. Such as powering off the system and quickly powering it back on again, that is what Restart button is for. Or if you are in the BIOS (or paused on-screen prior to entering your OS) and need to just restart, just press CTRL+ALT+DEL

If the PSU is plugged in however, the power is live via Standby power.
Turn off the main PSU switch and after a few minutes of being off this way, the power will leave the PSU by itself.

[Spanky]

it's true. that battery is also what will put your time out.

[Bad 💀 Motha]

CMOS Battery holds all BIOS settings when main PSU is off; that is the function of the battery.

If the CMOS battery goes dead and the PSU was off, or you disconnect that without any battery installed and then power on again; the BIOS settings will most likely all be reverted back to defaults.

[[☥] - CJ -]

Alright so to finish up my part of this thread..

I replaced the battery, tested the PSU, tested with another PSU, and another cases Power Switch and the PC still wont turn on even though the motherboard is getting power.

So i'm guessing its an issue with the board.. It is an old Dell from 2007/8 that had Vista on it, so eh..

But the good news is, strangely enough that PC has quite a bit better of a CPU and Optical drive in it than the PC i was going to sell the friend that is having the PC issues

So i put the Q6600(Decent CPU for a sucky Dell i know) into the PC im selling her (it had a C2D), along with her SATA Optical drive (mine was IDE for some reason lol), and shes getting Win7 64bit instead of crappy Vista so thats pretty good i think..


Now i just have to wait for the CPU cooler i had to order as mine either didnt fit or the plastic grabby pins broke off due to age and use, and hers didnt fit due to the motherboard layout lol..

Fun times..

But yeah.. thanks for tryin to help guys..


OH 1 more thing.. How much do you guys think i should sell it for? shes not trying to spend like $400 or so on a new PC.. it has

Her CPU Q6600
My 4GB RAM with 2x1GB sticks of hers to make 6GB(From 4GB)
My ASUS Motherboard
My 9800GTX+(Which is still a pretty decent GPU)
My 500w PSU
My 500GB Samsung Spinpoint HDD
Her Optical Drive
And possibly her HDD so she can try to get some of her stuff back if needed

All in all i was thinking maybe $150?
It'll help towards my purchase of a GTX 1060

[DinoSmite]

Originally posted by Genghis KHAN:

For the last two years I couldn't figure out why my three year old computer wouldn't boot. It wouldn't turn on after a power outage. And even if I did properly shut down the computer the night before, it still wouldn't turn on the next morning. I would have to drain the computer by disconnecting the PSU. At first it was a few minutes, then it gradually took a whole day for the computer to drain, then only would the computer boot up. What confused me was the computer worked like a champ when the computer decided to power on.

Then just last week my computer acted even more strange than what I've described above. The computer would power up after pressing the power button but then it would immediately shut down after two seconds. I looked online and the comments were mostly, "The culprit is most likely the PSU. You need to test your computer with another PSU."

Another person with similar computer issues like me jumped through loops with the advice they gave him online, e.g. re-seat hardware, install another PSU, etc. None worked so he decided to change CMOS battery. The computer then worked like a champ again and has no problem booting. And so did this too work for me. No costly unnecessry PSU, CPU, RAM, MOBO replacement.

Anyone has any theories as to why a weak CMOS battery would prevent the computer from booting and shutting down mid way before a complete boot? It's ridiculous. You will not find this advice on the web that the CMOS battery could be the culprit because as they explain, "The purpose of the CMOS battery is to only hold date and time. A dead or weak CMOS battery will not prevent the computer from booting. You'll just lose date and time."

I can confirm this I have an MSI motherboard that refuses to start when no battery is in. When the battery is low it will hardlock the computer, and then it will power up but refuse to fully boot.
There are no beeps and no notices,

my model is H61M-E33/W8

I disasembled the computer part by part, until the only thing that could be wrong would be the battery, and when I took it out it refused to boot, then googled it and found this thread and 2010 website post saying the samething, so on THANKSGIVING I went to wallgreens on 3pm bought a battery for 6 bucks and problem solved.

& I still cant believe the guide on tomshardware.com says to RMA the motherboard, christ facepalm.