[SOLVED] Is it necessary to jump short clear the CMOS for changing the CR2032 battery?

Diano

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Dec 5, 2014
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My PC is stuck dead at start when the brand logo appears.

One of the many diagnostic suggestions is to change the CR2032.

Some say it is necessary to short clear the CMOS prior to putting the new battery in.
Others say simply take the old one out and put the new one in. That is all.

What is the right way to do this? Is it necessary to short clear the CMOS by the jumper on the board?
 
Solution
Spam the Delete key, starting right after you push the power button. If Windows starts to load, you missed it.

F5 is almost always the key to set factory optimized settings, F10 is almost always 'save and exit'. Do that first. Then repeat going back into bios and change any required storage or ram xmp settings. Dont make too many changes with each bios save, keep it simple.

Pull power cord, hold power button for 20 seconds, then pull the battery out. Carefully! Then replace, Carefully, and make sure it's fully seated and you didn't bend any of the spring tabs. It doesn't just 'drop in', you'll need to find the tabs and insert at an angle so that they make good contact. Just that in itself will clear the cmos and reset the bios...
My PC is stuck dead at start when the brand logo appears.

One of the many diagnostic suggestions is to change the CR2032.

Some say it is necessary to short clear the CMOS prior to putting the new battery in.
Others say simply take the old one out and put the new one in. That is all.

What is the right way to do this? Is it necessary to short clear the CMOS by the jumper on the board?
No, taking that battery out clears CMOS and BIOS goes to factory default settings.
 
My PC is stuck dead at start when the brand logo appears.

One of the many diagnostic suggestions is to change the CR2032.

Some say it is necessary to short clear the CMOS prior to putting the new battery in.
Others say simply take the old one out and put the new one in. That is all.

What is the right way to do this? Is it necessary to short clear the CMOS by the jumper on the board?
There are different methods for this.
Here's a method.
Unplug input power.
Remove the bios bat.
Write down the number.
Go to the store and buy a new bat.
When you come back press and hold the pc power button for 20 secs.
Install new bat.
Connect input power and power up.
See if you can get into the bios.
 

Paperdoc

Polypheme
Ambassador
To be a little more complete, once you CAN get into BIOS by holding down the "Del" key, go to the Exit Menu for most mobos, There you will see that one of several options is to Load Factory Defaults or to Load Optimized Defaults. Do that. Then go back to the Main Menu. Look through the various BIOS sections to re-establish any custom settings you need, like which storage device to boot from. When done, return to the Exit Menu and choose to SAVE and EXIT. This will save your new settings and reboot cleanly.
 

Karadjgne

Titan
Ambassador
Spam the Delete key, starting right after you push the power button. If Windows starts to load, you missed it.

F5 is almost always the key to set factory optimized settings, F10 is almost always 'save and exit'. Do that first. Then repeat going back into bios and change any required storage or ram xmp settings. Dont make too many changes with each bios save, keep it simple.

Pull power cord, hold power button for 20 seconds, then pull the battery out. Carefully! Then replace, Carefully, and make sure it's fully seated and you didn't bend any of the spring tabs. It doesn't just 'drop in', you'll need to find the tabs and insert at an angle so that they make good contact. Just that in itself will clear the cmos and reset the bios. Manually resetting after is mostly redundant, but seriously cannot hurt to do, just to cover your a...

Resetting cmos by itself isn't a guaranteed fix, different components and software have different requirements and often are not the same as factory default. Things like CSM might be factory enabled, but an nvme requires that be disabled, boot to OtherOS in boot options might be enabled, but nvme require WinOS instead. For example.
 
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Solution
Thank you.

My PC is already dead, stuck at start when acer logo appears.

"... BIOS goes to factory default settings."
Does this apply to a PC already dead?

Thanks.
Depends how "Dead" it is, resetting CMOS by removing battery or shorting posts just sets CMOS to factory BIOS settings including date/time etc. If it's "Dead" because of some physical malfunction, that will not help.
Just try what others suggested and if that doesn't help you have more troubles than just BIOS settings.