CPU/Mobo Revert to Old BIOS after BIOS update

[Skyh3ck]

Hey guys

I recently I updated BIOS on my Lenovo laptop and Asus Laptop.. Lenovo worked fine but Asus got bad.. and did not power up after BIOS update.. later had to take it to service center to fix. They fixed in couple of hours.

My questions is once we update the BIOS ob laptop or desktop motherboard and if we want to go back to old BIOS version .. can we do it.

Or BIOS update is permanent.. can not be revert back to old version...

When we update BIOS do the system make any backup of old one.. just in case we want to go back to old version ?

Please help me with this..

Also what is difference between BIOS and EC version in motherboard...

 

[nRiTeCh]

Laptops I'm not sure but for desktops we can. Laptops it might be possible but with some other way..
I have dealt successfully with bios mods, dead bios etc. but only on desktops.

Still how much did the service center charged you?

 

[Skyh3ck]

Laptops I'm not sure but for desktops we can. Laptops it might be possible but with some other way..
I have dealt successfully with bios mods, dead bios etc. but only on desktops.

Still how much did the service center charged you?

No charge.. it s under warranty..

But does it make any backup for us when we flash new BIOS

I saw many people in service center with Asus laptop having issues with BIOS .. seems something wrong with Asus BIOS update

 

[nRiTeCh]

Yes one can backup old bios. Try your manufacturer utility, it usually gives that option to backup before flashing latest one.

 

[BluDev]

all BIOS updates can be flashed back to any older version quite easily if your Laptop /Computer is able to boot into bios
It gets tricky if your new bios is crashing and not letting you boot up at all even past the POST

 

[enthusiast29]

I wouldn't advise doing this to anyone unless you're absolutely sure and it's written by manufacturer that BIOS downgrade is supported.
Many manufacturers state that you cannot downgrade BIOS after a certain version (like in AMD after a certain AGESA version downgrade is not possible).

If attempted it's either denied or you'll end up with a brick. My old A320 chipset mobo died this way and sadly there was no way to recover it unless the EEPROM was swapped from a donor board or external BIOS programmer.

 

[BluDev]

Well most desktop boards will always have atleast the last multiple BIOS available for end users to install, (from their official site) specially sometimes after a new bios if thwre is conflict with some hardware users wanna go back to earlier version for trouble shooting
Have done the same many times across diff boards.
Again this is only if the motherboards POSTS and allows access to BIOS and this is predominantly fr my experience with Desktop motherboards

 

[Titokhan]

My questions is once we update the BIOS ob laptop or desktop motherboard and if we want to go back to old BIOS version .. can we do it.

Depends. If you've a hardware programmer, you should be able to make a complete backup of the existing firmware and restore it afterwards. In fact, a hardware-based solution is vastly superior than typical software flashers because the user can have full control on the flashing process (e.g. changing parameters that are otherwise not accessible to end users).

Or BIOS update is permanent.. can not be revert back to old version...

Technically, no.

However, the BIOS on a modern platform is quite a complex piece of software. Manufacturers often bundle additional firmware for co-processors (such as Intel ME) and microcodes for newer generations of CPUs with the BIOS image. Now, from the perspective of platform security as well as the complexities involved in the ROM re-writing phase through a regular software flasher, it would be easier to put an official "block" on downgrading past a specific build.

Having said that, you can still revert back if you have access to appropriate flashing utility and have studied the target platform thoroughly.

When we update BIOS do the system make any backup of old one.. just in case we want to go back to old version ?

It is subject to the OEM-provided flashing utility - some does, some doesn't. However, there exist both first-party (e.g. Intel FPT) and third-party applications that can perform the backup of an existing BIOS image.

Also what is difference between BIOS and EC version in motherboard...

Evolved from the keyboard controller, the embedded controller (EC) is a core component of low-power embedded devices (such as laptops). The EC is always on when power is supplied to the motherboard, performing a range of Input/Output (I/O) and system management functions. To reduce design complications, the EC's instructions are stored in a separate ROM chip other than the BIOS chip on traditional laptops.

@enthusiast29

If you still have the board in your possession and want to revive it, please drop me a message.

 

[Skyh3ck]

Thanks man...

What is CMOS clean up... I read removing battery from motherboard can revert back to factory bios..

How that works
Thanks man...

What is CMOS clean up... I read removing battery from motherboard can revert back to factory bios..

How that work

 

[Titokhan]

@Skyh3ck

You read it wrong.

Complementary metal-oxide-semiconductor (CMOS) is a small amount of memory on a computer motherboard that stores the BIOS/firmware settings. The CMOS can be reset using a CMOS jumper or a dedicated jumper on the motherboard, or by removing the battery. Such an event restores the BIOS default settings, but it is not possible to restore a previous BIOS image using CMOS reset.

The jumper position, time to wait, and location of the jumper are completely dependent on the motherboard. In case of laptops, resetting CMOS is a bit complicated due to the presence of the EC and other security measures.