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BIOS ROM Size Limitations Almost Derail AMD's Zen2 Backwards Compatibility Promise

On some boards you can drop new ones in, sure. That isn't close to a majority though. Most are soldered on the board.
damn, i know my z97 board can, if people have a spare am4 dual bios board someone should attempt a mod, and then patch the uefi together for r_ 3000 support
 
Yes, they chose RGB to market over spending $0.7 more on a better SPI chip. Guess what? Enthusiasts will now prefer those brands that chose 256Mb chips way back when designing their 300-series/400-series boards (eg: ASUS, ASRock), over brands that cheaped out (eg: MSI, GbT). Also, those buying a Zen2 processor with a brand new X470 chipset motherboard will avoid boards with 128Mb ROMs like cancer. I'm sure some based nerd on Reddit will compile a list of motherboards with ROM sizes to help others out.
I was thinking of buying either MSI B450M Bazooka Plus or AsRock B450M Steel Legend. But looks like both of them are 16MB bios chips. Even Tomahawk is only 16MB. I don't know what to choose any more.
 
I was thinking of buying either MSI B450M Bazooka Plus or AsRock B450M Steel Legend. But looks like both of them are 16MB bios chips. Even Tomahawk is only 16MB. I don't know what to choose any more.
If possible wait a bit more, save up a bit more cash and take any motherboard with 32MB eeprom.

I just checked and seems like all asrock's b450 matx motherboards are 16MB but Fatal1ty X470 Gaming-ITX/ac has 32MB module. Yes, i am aware it is itx so probably something what you are not interested in. All gigabyte's matx motherboards are 16MB. Another itx with 32MB is asus ROG STRIX B450-I GAMING. Biostar b450 and x470 matx boards have support for latest zen 2 and there is no info about anything removed from bios so i would assume these have 32MB but they do not list in specification eeprom sizes.
 
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I was thinking of buying either MSI B450M Bazooka Plus or AsRock B450M Steel Legend. But looks like both of them are 16MB bios chips. Even Tomahawk is only 16MB. I don't know what to choose any more.
I'd just wait for the B550 instead ;)
 
I've always disliked the new bios crap.

Simple text menu's is my preference, drop mouse support while at it, make them speedy as they used to be!
 
The size doesn't even matter. They could make different versions that only support one or the other. Gee, maybe if every board had flashback, then it would be a nonissue 100%.
 
I'm sure some based nerd on Reddit will compile a list of motherboards with ROM sizes to help others out.
Yeah, that's already been done. It's not quite complete, but it contains almost all of the collected knowledge of AM4 motherboards on this planet...
Note that it might take a while to load that spreadsheet.

Judging by that list, no 300-series chipset boards have more than 128Mbit.

Interestingly, that means my board only has 128Mbit, yet Asus still seems to claim support for all features...
 
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Two sets of BIOSes will require some type of dual-BIOS switching or Flashback functionalities to be reasonably useful. Getting a different supported CPU to get the BIOS upgraded on the motherboard you just purchased to support a CPU you also just purchased is annoying enough already, making this standard operating procedure is not a good idea.

Most modern mb bios can be flashed without even powering a system on or even having a cpu in the socket.
 
i wonder why the manufacturers can't simply make multiple BIOS branches
1. for APUs
- for first gen
- for second gen
2. for CPUs
- for first gen
- for second gen
- for third gen

if the ROM is too small then branching it like this is logical to save as much space as possible
while each of them could be it's own version

same for RAID, i remember times when some controllers and cards
had separated variants of with RAD and w/o RAID due to sizes

of course they could also get rid of theirs graphical logo and loading pictures bloat ;)

now i get the point of all-in-one being simple and risk free, but that does applies only if you got the ROM memory space ;)
 
Re: those talking about price difference:

According to DigiKey, an 8-pin 128Mbit (16 MB) SPI flash ROM chip of the kind used on motherboards starts at $1.31 a piece when bought in bulk reels. A 256Mbit (32 MB) chip in the same form-factor costs $2.04 a piece. Motherboard makers have the bargaining power to bring those prices down even further. Even if not, they're literally 70 cents apart. Motherboard designers could have cut out some RGB crap to make room for a 256Mb chip. They probably wanted forced-obsolescence by telling AMD "it can't be done" when the time came, but failed at that when AMD replied "it can be done, just delete support for older processors and make your setup program smaller."

No one was talking about price differences...

16MB roms are standard and fit nearly everything in the Intel realm (Microcode there is like... in kb size realm). I'm with others, this is more AMD not communicating how much AGESA would bloat. It has nothing to do with pricing or any other grand conspiracy to make us upgrade...

UEFI is a bloated piece of crap

Not inherenetly, but in pratice, it can be. It is however a security nightmare in 90% of implementations, yes. Not that bios was any better though...
 
this problem only effects msi and their bloated bioses. if you open any other bios image from say asus, asrock, or biostar youll find that there is plenty of empty space in those bioses. This article really only pertains to msi. everybody else is fine who does not own one of these boards. btw, everybody else uses 16mb roms too.
 
this problem only effects msi and their bloated bioses. if you open any other bios image from say asus, asrock, or biostar youll find that there is plenty of empty space in those bioses. This article really only pertains to msi. everybody else is fine who does not own one of these boards. btw, everybody else uses 16mb roms too.
No, gigabyte also removed support for older APUs but they didn't go that far and didn't remove as crucial functions as raid like msi did.
 
this problem only effects msi and their bloated bioses. if you open any other bios image from say asus, asrock, or biostar youll find that there is plenty of empty space in those bioses. This article really only pertains to msi. everybody else is fine who does not own one of these boards. btw, everybody else uses 16mb roms too.

That explains why my gigabyte modding days on AM4 found space aplenty...

No, gigabyte also removed support for older APUs but they didn't go that far and didn't remove as crucial functions as raid like msi did.

If true than the bloat got quite out of hand. My Gigabyte Aorus X370 Gaming 5 had a lot of free space at launch.
 
No, gigabyte also removed support for older APUs but they didn't go that far and didn't remove as crucial functions as raid like msi did.

i just looked at the gigabyte ab350m gamming 3 bioses from before 2nd gen support and now and there is enough space in the bios for them to have not needed to remove anything from it. i think its the manufactures being lazy and not wanting to restructure the bios for older boards. if gigabyte wants to add support back in later on then they should be able too. msi on the other hand needs an entirely new structured lightweight bios but that would cost money that they not willing to invest into an old platform.
 
Yeah, that's already been done. It's not quite complete, but it contains almost all of the collected knowledge of AM4 motherboards on this planet...
Note that it might take a while to load that spreadsheet.

Judging by that list, no 300-series chipset boards have more than 128Mbit.

Interestingly, that means my board only has 128Mbit, yet Asus still seems to claim support for all features...

Same here.
My ASUS x370-i listed in the spreadsheet having 128Mb Flash ROM, BIOS version 5008 running a 3700x so far so good.
 
Yeah, that's already been done. It's not quite complete, but it contains almost all of the collected knowledge of AM4 motherboards on this planet...
Note that it might take a while to load that spreadsheet.

Judging by that list, no 300-series chipset boards have more than 128Mbit.

Interestingly, that means my board only has 128Mbit, yet Asus still seems to claim support for all features...
A god no less prepared that spreadsheet...
 
All this so manufacturers can save 3c per board... The greed, man!

No, no, you got it wrong. It's so they can spend that money on RGB LEDs, as it's a far more important feature...
 
A god no less prepared that spreadsheet...
According to that spreadsheet even not all x570 are using 32MB modules and many of them have 16MB... That's bad. And some of them are not cheap.
 
According to that spreadsheet even not all x570 are using 32MB modules and many of them have 16MB... That's bad. And some of them are not cheap.
But the X570 does not need support for the original Zen ;)
 
But the X570 does not need support for the original Zen ;)
What do you mean by that? As far as i am aware x570 has compatibility from latest ryzen 3xxx series down to first ryzen cpus.
 
What do you mean by that? As far as i am aware x570 has compatibility from latest ryzen 3xxx series down to first ryzen cpus.
Nope. Look it up on AMD's website: only Zen+ and Zen2 are supported.
 
I have the msi x370 gaming pro carbon.
last week had released a bios and then updated with my old cpu 1600x 1600x.
worked perfectly with the 1600x until then.
But the following week this bios was removed!
Now I sold my 1600x r5 and bought the 3900x r9, I'm waiting to arrive.
In bios says the following

This BIOS fixes the following problem of the previous version:
- Update AMD ComboPI1.0.0.1
- Support new upcoming AMD cpu.

So my new cpu will work or at least post so that I can upgrade to newer bios?
 
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