Tuesday, May 19th 2020

AMD Backpedals, Zen 3 Support Coming to B450 and X470

AMD backpedaled on dropping support for its future "Zen 3" processors on AMD 400-series chipset motherboards. The company will work with its motherboard partners in integrating "Zen 3" processor support on certain beta versions of motherboard BIOSes. AMD also detailed how it plans to go about it. The said BIOS will be a one-way ticket to using "Zen 3" processors while losing support for all older microarchitectures.

The way it works is the motherboard manufacturer will integrate the Zen 3-only AGESA with a firmware that can squeeze into a 16 MB ROM. They may also choose to conserve ROM space in areas such as the UEFI setup program, which may not correspond with the motherboard's original feature-set. This is essentially similar to how MSI integrated "Zen 2" support on some of its older motherboards with 16 MB ROMs, by slimming down its UEFI setup program.

Since the BIOS will chop support for all older processors, to prevent motherboard RMA chaos for manufacturers, they will set up a system that issues BIOS updates only to customers upon verifying that they actually own a "Zen 3" processor. The way we imagine this works would be similar to game bundles (retailer issues a BIOS update token along with the processor, or a scratch card next to the case badge inside the PIB). Flashing a 400-series chipset motherboard will be a delicate process. You will have to use the USB BIOS flashback feature (which luckily is well proliferated on the AM4 motherboard ecosystem). Alternatively, you should be able to begin the BIOS flashing process with an older processor installed, and immediately switch over to the newer Zen 3 processor once the flashing process is complete.

Also, the beta BIOS updates won't be immediately available, but rather when "Zen 3" processors are readily available in all the markets AMD serves. AMD reiterates, that "Zen 3" will be the final microarchitecture 400-series chipsets support, recommending that the processors will work best with a 500-series chipset motherboard for best performance and support for the latest features.

Controversy erupted when AMD revealed in its B550 chipset slide deck that 400-series (and older) chipsets won't support "Zen 3," which users felt betrayed AMD's promise of platform support running into 2020. In the absence of B550, many value-conscious buyers paired their brand new 3rd generation Ryzen processors with some of the more premium B450 chipset motherboards, in hopes of an upgrade path to "Zen 3."
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93 Comments on AMD Backpedals, Zen 3 Support Coming to B450 and X470

#2
bug
With all that talk, AMD was about to do what their fans accuse Intel of: removing CPU support for no good reason.
At least they reversed their stance quickly. But not quick enough for people not to notice where their heart truly is ;)
Posted on Reply
#3
Mats
bug
But not quick enough for people not to notice where their heart truly is ;)
Dunno about that. I mean, how official was that reddit post to begin with? Yeah he worked for AMD, but I have no more info than that.

This wasn't a simple yes/no question. AMD really had to give it a thought if it was feasible, and to what extent.
Posted on Reply
#6
KarymidoN
I Have a question, legit one, might be stupid but if anyone can answer...

My Mobo has Dual Bios (2 16mb chips), a lot of Mobos do. I Can have 2 complete different versions of bions on those 2.
Why not create an option to update the second bios to ZEN3 while using the #1 BIOS for ZEN/ZEN+/ZEN2?
and if you try to boot BIOS#1 with ZEN3 it detects and tryies the BIOS#2...

Is that not possible? too risky? legit question.
Posted on Reply
#7
thesmokingman
KarymidoN
I Have a question, legit one, might be stupid but if anyone can answer...

My Mobo has Dual Bios (2 16mb chips), a lot of Mobos do. I Can have 2 complete different versions of bions on those 2.
Why not create an option to update the second bios to ZEN3 while using the #1 BIOS for ZEN/ZEN+/ZEN2?
and if you try to boot BIOS#1 with ZEN3 it detects and tryies the BIOS#2...

Is that not possible? too risky? legit question.
It's going to be up to board p[artners to do the soft lifting to make it work. There are too many if ands or buts which is why they said no. But really it is going to come down to the board partners to sort it all out.
Posted on Reply
#8
bug
KarymidoN
I Have a question, legit one, might be stupid but if anyone can answer...

My Mobo has Dual Bios (2 16mb chips), a lot of Mobos do. I Can have 2 complete different versions of bions on those 2.
Why not create an option to update the second bios to ZEN3 while using the #1 BIOS for ZEN/ZEN+/ZEN2?
and if you try to boot BIOS#1 with ZEN3 it detects and tryies the BIOS#2...

Is that not possible? too risky? legit question.
You don't need an option for that, you can already flash anything you want on your BIOS copies. Typically one copy is used as backup/failsafe, but they don't care which BIOS version they hold. But you'll loose the backup/failsafe if the other copy doesn't support your current CPU.
Posted on Reply
#10
TheLostSwede
KarymidoN
I Have a question, legit one, might be stupid but if anyone can answer...

My Mobo has Dual Bios (2 16mb chips), a lot of Mobos do. I Can have 2 complete different versions of bions on those 2.
Why not create an option to update the second bios to ZEN3 while using the #1 BIOS for ZEN/ZEN+/ZEN2?
and if you try to boot BIOS#1 with ZEN3 it detects and tryies the BIOS#2...

Is that not possible? too risky? legit question.
Maybe, on some boards it's possible, but not on all. You also can't manually select which one to boot from on most boards. Your board doesn't appear to have such a switch. Normally only really high-end models have that.
Posted on Reply
#11
ZoneDymo
bug
With all that talk, AMD was about to do what their fans accuse Intel of: removing CPU support for no good reason.
At least they reversed their stance quickly. But not quick enough for people not to notice where their heart truly is ;)
you should really look into the problem before running your mouth, would make you look a tad more intelligent.
I recommened Gamers Nexus.
Posted on Reply
#12
moproblems99
thesmokingman
It's going to be up to board p[artners to do the soft lifting to make it work. There are too many if ands or buts which is why they said no. But really it is going to come down to the board partners to sort it all out.
My understanding was that it was only an issue based on UEFI rom size.
Posted on Reply
#13
TheLostSwede
bug
You don't need an option for that, you can already flash anything you want on your BIOS copies. Typically one copy is used as backup/failsafe, but they don't care which BIOS version they hold. But you'll loose the backup/failsafe if the other copy doesn't support your current CPU.
How do you, as the end user, flash the secondary chip, if there's no switch to select which one to flash?
Normally it seems to be a matter you being able to flash the primary chip, but not the secondary one. I haven't had my secondary one kick in for so long that I don't even remember if gets flashed automagically or doesn't get updated at all.
Posted on Reply
#14
bug
Mats
That's not reddit. I was referring to when some AMD guy said the opposite of what that pic says, which started this whole shit storm.
You lost me.
Posted on Reply
#15
thesmokingman
moproblems99
My understanding was that it was only an issue based on UEFI rom size.
The main issue is that the early Ryzens do not support ROM over 16mb. These cpus will see a 32MB ROM as two 16MB partitions if you will. That's why I suspect it will come down to how much lifting board partners are going to put into it. There's way too many variables times the cpus out there, times the MB models.
Posted on Reply
#16
bug
TheLostSwede
How do you, as the end user, flash the secondary chip, if there's no switch to select which one to flash?
Normally it seems to be a matter you being able to flash the primary chip, but not the secondary one. I haven't had my secondary one kick in for so long that I don't even remember if gets flashed automagically or doesn't get updated at all.
I'm not sure. I'm running Z170, I haven't flashed in a while...
Posted on Reply
#17
Mats
moproblems99
My understanding was that it was only an issue based on UEFI rom size.
Partly, the other one being that all CPU's before Ryzen 3000 can only read 16 MB ROMs.
Posted on Reply
#18
NoJuan999
KarymidoN
I Have a question, legit one, might be stupid but if anyone can answer...

My Mobo has Dual Bios (2 16mb chips), a lot of Mobos do. I Can have 2 complete different versions of bions on those 2.
Why not create an option to update the second bios to ZEN3 while using the #1 BIOS for ZEN/ZEN+/ZEN2?
and if you try to boot BIOS#1 with ZEN3 it detects and tryies the BIOS#2...

Is that not possible? too risky? legit question.
It can be done on some motherboards BUT you will need to have the know how to flash the back up (2nd BIOS ROM) separately from the main BIOS ROM.
I did exactly that on a Gigabyte P55A board.
I had a BIOS version that I modified on the main ROM and the original untouched BIOS on the backup ROM.
Mine required using a DOS flash utility and using the correct software switches to flash the back up BIOS.
It did NOT have a physical switch to do that.
Posted on Reply
#19
TheLostSwede
moproblems99
My understanding was that it was only an issue based on UEFI rom size.
Well, sort of. I mean, the board makers are also going to have to be willing and it's possible and this is pure speculation, that they approached AMD and said hey, we didn't put large enough flash chips for the UEFI on these boards, so we don't want to support them for your next gen CPUs. Obviously the way it is now, it's down to each board makers to decide which boards may or may not get support, which sort of absolves AMD and the board makers.
Posted on Reply
#20
moproblems99
thesmokingman
The main issue is that the early Ryzens do not support ROM over 16mb.
Not necessarily a problem when an early Ryzen is not what is going back in to the board.
Posted on Reply
#21
thesmokingman
moproblems99
Not necessarily a problem when an early Ryzen is not what is going back in to the board.
You are not getting it. The early boards were not made with 32MB ROMS cuz the cpus only addressed up to 16MB. Board partners are going to have to make news bios per MB per needs.
Posted on Reply
#22
Mats
bug
You lost me.
Yeah, I didn't know about it until last week. At 7:40.
Posted on Reply
#23
GoldenX
Oh no, get ready for another round of broken BETA BIOS that no one will ever fix.
Posted on Reply
#24
Assimilator
I'm 100% sure this won't turn out to be a s**tshow like everything BIOS-related with AMD before (AGESA stability, MSI 16MB BIOS limits, RX 5600 XT memory OC).
Posted on Reply
#25
evernessince
bug
With all that talk, AMD was about to do what their fans accuse Intel of: removing CPU support for no good reason.
At least they reversed their stance quickly. But not quick enough for people not to notice where their heart truly is ;)
Wrong. Go watch GamersNexus videos on the topic. AMD removing support for last gen was a shit move but there were multiple legitimate reasons why they would need to do it.
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