Question ASUS BIOS update for AMD mobos: "You will not be able to downgrade your BIOS after updating to this BIOS version"

yeshua

Member
Aug 7, 2019
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ASUS has recently released multiple BIOS updates for its AMD motherboards many of which feature this scary message:

"You will not be able to downgrade your BIOS after updating to this BIOS version"

no-downgrade.png


Could anyone please explain 1) whether there's really no option to downgrade BIOS and 2) how this limitation is even possible in the first place.

Some people on Reddit/ASUS own forums claim that they are still able to downgrade their BIOS despite this message. Is it really safe? What the consequences could be?

And some say that "combo PI 1.0.0.4 patch B" made their RAM stop working at the specified manual speeds/timings, so I'm a little bit scared 'cause my RAM is overclocked.
 

UsandThem

Elite Member
May 4, 2000
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Asrock has the same message for both Intel and AMD systems.
Yup, I've seen the same thing from all motherboard manufacturers.

it is possible to go back to an older version, but it's not as simple as just flashing back to a prior version.
 

yeshua

Member
Aug 7, 2019
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Can I have answers to my questions please? Observations, speculation and advice are not what I was asking for. I'm old enough to make reasonable choices.
 

VirtualLarry

No Lifer
Aug 25, 2001
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and 2) how this limitation is even possible in the first place.
Modern flash BIOSes, have various "Segments", that also correspond with capacity divisions within the flash chip. Some, usually at the end of the chip, hold the bootblock. Others hold the init code, still others hold the "modules" for the onboard hardware, and then there are segments that hold "modifiables", for lack of a better name. Stuff like the ESCD and DMI info tables.

Sometimes, the arrangement of those segments within the physical BIOS chip fitted to the motherboard changes. Hence the "infamous" ASRock "Bridge BIOS" versions, for their AM4 boards, that you must flash, before flashing the newer ones, and then can't go backwards.
 

Kenmitch

Diamond Member
Oct 10, 1999
8,505
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Modern flash BIOSes, have various "Segments", that also correspond with capacity divisions within the flash chip. Some, usually at the end of the chip, hold the bootblock. Others hold the init code, still others hold the "modules" for the onboard hardware, and then there are segments that hold "modifiables", for lack of a better name. Stuff like the ESCD and DMI info tables.

Sometimes, the arrangement of those segments within the physical BIOS chip fitted to the motherboard changes. Hence the "infamous" ASRock "Bridge BIOS" versions, for their AM4 boards, that you must flash, before flashing the newer ones, and then can't go backwards.

That sounds good enough for the why, but why worry about the why if you can find the how anyways?

Both of my AMD mb's have the usb flashback feature so I've never worried about trying out the latest and possibly greatest versions as I have a built in way back anyways.

There's a video on youtube that says it'll let you downgrade Asus mb's bios.

 

UsandThem

Elite Member
May 4, 2000
16,068
7,380
146
Can I have answers to my questions please? Observations, speculation and advice are not what I was asking for. I'm old enough to make reasonable choices.
We are so sorry to offend you while helping you for free. :rolleyes:

Just because you've never encountered that BIOS update warning before doesn't mean we haven't.

Google results
 
Last edited:

yeshua

Member
Aug 7, 2019
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That sounds good enough for the why, but why worry about the why if you can find the how anyways?

Both of my AMD mb's have the usb flashback feature so I've never worried about trying out the latest and possibly greatest versions as I have a built in way back anyways.

There's a video on youtube that says it'll let you downgrade Asus mb's bios.
My ASUS motherboard doesn't have a BIOS flashback feature and almost all new software (BIOS is also software) has bugs, so I'm kinda concerned. At the same time new BIOS versions are usually released to fix bugs, so I feel like I'm between a rock and a hard place.

Also, last time I tried to downgrade BIOS around 10 years ago, I killed the BIOS region which was responsible for the NIC MAC address and in order to use networking I had to manually assign a MAC address to my NIC on every cold boot. Anyways, I'll just wait a few weeks and see if people have bugs with this new BIOS and if they don't, I'll upgrade to it.
 

Kenmitch

Diamond Member
Oct 10, 1999
8,505
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My ASUS motherboard doesn't have a BIOS flashback feature and almost all new software (BIOS is also software) has bugs, so I'm kinda concerned. At the same time new BIOS versions are usually released to fix bugs, so I feel like I'm between a rock and a hard place.

Also, last time I tried to downgrade BIOS around 10 years ago, I killed the BIOS region which was responsible for the NIC MAC address and in order to use networking I had to manually assign a MAC address to my NIC on every cold boot. Anyways, I'll just wait a few weeks and see if people have bugs with this new BIOS and if they don't, I'll upgrade to it.

Nothing wrong with waiting for others to test the waters before you jump in.

I'm a tinkerer and can't resist testing the latest and possibly not so greatest uEFI versions that drop. I doubt I'll ever buy another MB without the usb flashback feature baked in.

It's been hit and miss on the Asus Crosshair VI Hero uEFI's I've tried so far. They just launched a newer one for my C6H recently that I'm currently trying out. The last one wasn't so good with my ram at 3700 with a 1:1 divider. I just installed the latest one a little while ago and haven't played around with it too much yet.
 

JimKiler

Diamond Member
Oct 10, 2002
3,558
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I installed this BIOS last week and no issues so far.
ASUS has recently released multiple BIOS updates for its AMD motherboards many of which feature this scary message:

"You will not be able to downgrade your BIOS after updating to this BIOS version"

View attachment 13083


Could anyone please explain 1) whether there's really no option to downgrade BIOS and 2) how this limitation is even possible in the first place.

Some people on Reddit/ASUS own forums claim that they are still able to downgrade their BIOS despite this message. Is it really safe? What the consequences could be?

And some say that "combo PI 1.0.0.4 patch B" made their RAM stop working at the specified manual speeds/timings, so I'm a little bit scared 'cause my RAM is overclocked.

I upgraded last week and have yet to notice any issues.
 
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