iM 4,1-14,4 2011 iMac Graphics Card Upgrade

[Ausdauersportler]

Thanks all for this amazing work and research !
I've bought myself an HP K1100M and installed the new GPU in my iMac mid 2011 (21,5"). On first boot I disconected the SSD and booted the USB (by xanderon) to flash the GPU with the K1100.rom beta 1.2 (by Nick).
All this went perfect and my iMac is booting High Sierra 10.13.6 (start screen works by using option key).
But now, before proceeding, I wanted to do a fresh and clean install, but I can't get it working. So I tap the option key, and once screen comes up I used both Command-R / Command-Shift-option-R. Internet recovery starts, I get the Apple logo and circle, but that's it, nothing happens .
I am not sure if I have the latest firmware (BootROM 87.0.0.0.0 ; SMC 1.71f22), and I would like to be able to have a fallback if things go wrong.
What would you suggest ?

I guess you have to enter your WiFi key to connect the iMac to you home network or you connect the iMac using a cable to the router.

The other option would be to download the macOS installer you need using by using a @dosdude1 High Sierra patcher (just let it download the original apple installer) or the gibMacOS utility...

 

[iceberg411]

W5170M​

Can you tell me if I can adjust the brightness with this video card and see the boot screen?

I want to buy it and try it. What do I need for this?

 

[vastunghia]

Disable SIP and try again.

Oooops, sorry, forgot to mention that SIP was disabled already. Will edit my post.

Thank you anyway.

Anyone else?

 

[Ausdauersportler]

W5170M​

Can you tell me if I can adjust the brightness with this video card and see the boot screen?

I want to buy it and try it. What do I need for this?

Nothing you can get on this thread. Go back to post #1 one and read about the cards known to run in theses iMacs.

 

[Ausdauersportler]

Ciao,

this is driving me nuts.

I'm trying to backup my iMac11,2's ROM using dosdude's ROMtool.

This is exactly what I'm doing:

1. disable SIP
2. move the zip to Applications folder
3. unzip the app
4. open the app
5. select 'Dump System ROM'
6. insert root password

This is what I get: "Kext Error DirectHW.kext could not be loaded. The operation cannot proceed."

So if I look at the Console, I see two repeated log entries from kextd stating that "/Users/[myusername]/Library/Application Support/ROMTool/DirectHW.kext has no Info.plist file."

So from Terminal, I try to head to /Applications/ROMTool.app/Contents/Resources/, and issue a sudo kextload DirectHW.kext. In this case Terminal returns "failed to load - (libkern/kext) authentication failure (file ownership/permissions)", and Consoled reads "Kext rejected due to improper filesystem permissions".

So I try sudo -R chmod 755 DirectHW.kext and sudo -R chown root:wheel DirectHW.kext, and once again sudo kextload DirectHW.kext. This works! Console reads "Kext with invalid signatured (-67062) allowed".

So next, sudo kextunload DirectHW.kext, head over to ~/Library/Application Support/ROMTool/, and first, as a check, sudo kextload DirectHW.kext: as expected, same error as above regarding missing Info.plist.

So the idea is: I have a kext that loads fine in /Applications, and one that does not in ~/Library. Let's simply replace the latter with the former!

Then, still under ~/Library/Application Support/ROMTool/, sudo rm -R DirectHW.kext, followed by sudo cp -R /Applications/ROMTool.app/Contents/Resources/DirectHW.kext /Users/[myusername]/Library/Application\ Support/ROMTool/. Then, finally, sudo kextload DirectHW.kext.

It should work now, right? But it doesn't!! I still get the "failed to load - (libkern/kext) not found" message in Terminal, and "/Users/[myusername]/Library/Application Support/ROMTool/DirectHW.kext has no Info.plist file" message in Console.

It seems like the very same kext is loading if put in one place (/Applications), but not in another (~/Library).

What am I doing wrong??

Or, alternatively, how can I go backup my ROM bypassing dosdude's GUI? After all, I was able to load the kext from Terminal. I just need to know what commands to issue in order to dump the ROM next.

Thanks in advance

Sergio

Please add a signature to your account with your hard- and software.

Copy the RomTool to your applications folder. Run it from High Sierra with SIP disabled or from Mojave/Catalina (SIP disabled by default after @dosdude1 installer used). Does not work on Big Sur.

The error is annoying, but we all made it work at the end. There is no secret knowledge necessary and you could have tried to search the thread for "romtool" in advance...

 

[iceberg411]

Please add a signature to your account with your hard- and software.

Copy the RomTool to your applications folder. Run it from High Sierra with SIP disabled or from Mojave/Catalina (SIP disabled by default after @dosdude1 installer used). Does not work on Big Sur.

The error is annoying, but we all made it work at the end. There is no secret knowledge necesarry and you could have tried to search the thread for "romtool" in advance...

Hi! with your iMac 27 Mid 2011 WX4170 i7-2600 Big Sur is worked?

 

[shasen1235]

you need stay offline and create a group polity using the specific hardware IDs of the iGPU. to do this go to device manager -> right click on video controller -> properties -> details tab and in the property drop down menu you will find "hardware ids" for the iGPU.

open gpedit.msc
navigate to Computer Configuration -> Administrative Templates -> System -> Device installation -> Device installation Restrictions and edit the policy called "Prevent installation of devices that match any of these device IDs"
Enabled it and click on "Show"
Copy and paste the Hardaware IDs of the iGPU (all 4 of them), click ok and the Apply.

The drivers will not install anymore, unless you trun the policy off. this will apply only to the iGPU as the hardware IDs are specific only for it

This is quite clever!
I'll give it a try!

 

[Ausdauersportler]

Hi! with your iMac 27 Mid 2011 WX4170 i7-2600 Big Sur is worked?

Obviously! Have you checked the first post and the section about the macOS installation?
Big Sur will work with every card list there.

 

[Ausdauersportler]

After rebooting it is still the same thing. Screen is dark, in few minutes I have voice over notification and to see my screen and setup my Big Sur I have to reboot into boot menu and manually boot into my main drive.

Nothing changes.I used older Big Sur installer to make bootable USB, I patched it with your patcher, erased my disc, installed Bog Sur, couple of times my iMac rebooted with black screen, after I felt that my iMac is cold and fans are spining just because I lack thermal sensor on my SSD I forced it to turn off and turned it on to install kexts and nothing works.

Before I force my iMac to reboot I wait at least an hour and once I waited 3h to make absolutely sure that I haven't interrupted installation process. Still nothing.

This is odd.

Try installing OpenCore on and SD card using the attached 0.6.5per config file (I assume you have patched the system already). On boot use alt/option and choose the SD card to boot while pressing CRTL (makes it default). Another boot selector will come up showing most likely only the Big Sur installation. Boot into it and check the Big Sur.

Then make a shut down and a cold start. The OpenCore should boot and switch on the LCD by default.

This config.plist will not load any extensions already installed on your system.

 

[vastunghia]

Please add a signature to your account with your hard- and software.

Copy the RomTool to your applications folder. Run it from High Sierra with SIP disabled or from Mojave/Catalina (SIP disabled by default after @dosdude1 installer used). Does not work on Big Sur.

The error is annoying, but we all made it work at the end. There is no secret knowledge necesarry and you could have tried to search the thread for "romtool" in advance...

Dear Ausdauersportler,

thank you for taking the time to answer.

Unfortunately, this is the third time you answer me with something like "you haven't read the first post, you should have looked around before posting, and anyway please find the solution by yourself as I did before you".

While actually in all of the occasions I had read the first post, I had looked around before posting, and if I decided to post, then you know?, it was just because I found no solution anywhere, and I hoped that there were people out there with more experience than me who were willing to help (otherwise, what this forum would be for?), instead of spending their time trolling newbies.

So at the end of the day your answers were empty presumption (presumption that, say, for sure I had not done my homework in advance): nothing less, nothing more. Adding no value to find a real solution for problems (or even simple doubts) that had never been tackled before.

[If I'm wrong, and you can provide a link to a post explaining exactly how to solve my specific issue with ROMtool, for instance, I will be glad to apologize of course. I was not able to find it.]

Finally, let me remark that if there is one who is posting without reading first, that seems to be you, since in all cases you overlooked important pieces of information that I posted regarding my specific situations.

Not sure whether you are doing all of this with the best intentions, or what. And maybe I was just unlucky in my interactions with you, while 99% of the time you provide brilliant solutions to everybody. But I find all of your answers to my posts to be very dysfunctional: they make people (yourself, in the first place, but of course also me and everybody else who is scrolling through the forum looking for real answers and solutions) waste a lot of time; and above all I think they deter other people from posting answers that could actually add some real value and help come up with real solutions.

So please, from now on, may I kindly ask you to ignore my posts? This is exactly what I will be doing with yours, whatever you may write in the future. Hope we can find this agreement.

Thank you

Sergio

 

[vastunghia]

Ciao,

this is driving me nuts.

I'm trying to backup my iMac11,2's ROM using dosdude's ROMtool.

This is exactly what I'm doing:

1. disable SIP
2. move the zip to Applications folder
3. unzip the app
4. open the app
5. select 'Dump System ROM'
6. insert root password

This is what I get: "Kext Error DirectHW.kext could not be loaded. The operation cannot proceed."

So if I look at the Console, I see two repeated log entries from kextd stating that "/Users/[myusername]/Library/Application Support/ROMTool/DirectHW.kext has no Info.plist file."

So from Terminal, I try to head to /Applications/ROMTool.app/Contents/Resources/, and issue a sudo kextload DirectHW.kext. In this case Terminal returns "failed to load - (libkern/kext) authentication failure (file ownership/permissions)", and Consoled reads "Kext rejected due to improper filesystem permissions".

So I try sudo -R chmod 755 DirectHW.kext and sudo -R chown root:wheel DirectHW.kext, and once again sudo kextload DirectHW.kext. This works! Console reads "Kext with invalid signatured (-67062) allowed".

So next, sudo kextunload DirectHW.kext, head over to ~/Library/Application Support/ROMTool/, and first, as a check, sudo kextload DirectHW.kext: as expected, same error as above regarding missing Info.plist.

So the idea is: I have a kext that loads fine in /Applications, and one that does not in ~/Library. Let's simply replace the latter with the former!

Then, still under ~/Library/Application Support/ROMTool/, sudo rm -R DirectHW.kext, followed by sudo cp -R /Applications/ROMTool.app/Contents/Resources/DirectHW.kext /Users/[myusername]/Library/Application\ Support/ROMTool/. Then, finally, sudo kextload DirectHW.kext.

It should work now, right? But it doesn't!! I still get the "failed to load - (libkern/kext) not found" message in Terminal, and "/Users/[myusername]/Library/Application Support/ROMTool/DirectHW.kext has no Info.plist file" message in Console.

It seems like the very same kext is loading if put in one place (/Applications), but not in another (~/Library).

What am I doing wrong??

Or, alternatively, how can I go backup my ROM bypassing dosdude's GUI? After all, I was able to load the kext from Terminal. I just need to know what commands to issue in order to dump the ROM next.

Thanks in advance

Sergio

Ok, so I went on and tried to figure out how to dump ROM from command line, since I was able to load DirectHW.kext from Terminal (still no clue why @dosdude1 's GUI is not able to load kext... the reason being that kext cannot be loaded when put in ~/Library... )

So after successfully loading DirectHW.kext, I issued sudo ./flashrom -p internal -r ROM_dump.bin, and this is what flashrom returns:

[...]
Found Macronix flash chip "MX25L3205(A)" (4096 kB, SPI) at physical address 0xffc00000.
Found Macronix flash chip "MX25L3205D/MX25L3208D" (4096 kB, SPI) at physical address 0xffc00000.
Found Macronix flash chip "MX25L3206E" (4096 kB, SPI) at physical address 0xffc00000.
Multiple flash chip definitions match the detected chip(s): "MX25L3205(A)", "MX25L3205D/MX25L3208D", "MX25L3206E"
Please specify which chip definition to use with the -c <chipname> option.

So after looking around I found out that the safest solution would be to determine my specific chipset by opening the iMac. If this is the only possibility to keep things safe, I will do that.

I was wondering, however, if I can avoid opening my iMac -- would be a pain in the neck to do that only for this, and after all, @dosdude1 's tool does not need to do that to dump ROM, so there must be an alternative... So my questions are:

1. Is it safe to use flashrom to read (only!) ROM by just guessing the chipname option? Do I risk bricking my system? Only by trying to read ROM?
2. If the answer to 1 is 'yes, it is safe', is flashrom going to alert me in case I guessed the wrong chipset? Or is it going to produce a bin file anyway, with no possibility to understand whether everything went fine or not?

Hope I was clear in my questions.

And thanks a lot in advance!

Sergio

 

[Pascal Baillargeau]

Ciao,

this is driving me nuts.

I'm trying to backup my iMac11,2's ROM using dosdude's ROMtool.

This is exactly what I'm doing:

1. disable SIP
2. move the zip to Applications folder
3. unzip the app
4. open the app
5. select 'Dump System ROM'
6. insert root password

This is what I get: "Kext Error DirectHW.kext could not be loaded. The operation cannot proceed."

So if I look at the Console, I see two repeated log entries from kextd stating that "/Users/[myusername]/Library/Application Support/ROMTool/DirectHW.kext has no Info.plist file."

So from Terminal, I try to head to /Applications/ROMTool.app/Contents/Resources/, and issue a sudo kextload DirectHW.kext. In this case Terminal returns "failed to load - (libkern/kext) authentication failure (file ownership/permissions)", and Consoled reads "Kext rejected due to improper filesystem permissions".

So I try sudo -R chmod 755 DirectHW.kext and sudo -R chown root:wheel DirectHW.kext, and once again sudo kextload DirectHW.kext. This works! Console reads "Kext with invalid signatured (-67062) allowed".

So next, sudo kextunload DirectHW.kext, head over to ~/Library/Application Support/ROMTool/, and first, as a check, sudo kextload DirectHW.kext: as expected, same error as above regarding missing Info.plist.

So the idea is: I have a kext that loads fine in /Applications, and one that does not in ~/Library. Let's simply replace the latter with the former!

Then, still under ~/Library/Application Support/ROMTool/, sudo rm -R DirectHW.kext, followed by sudo cp -R /Applications/ROMTool.app/Contents/Resources/DirectHW.kext /Users/[myusername]/Library/Application\ Support/ROMTool/. Then, finally, sudo kextload DirectHW.kext.

It should work now, right? But it doesn't!! I still get the "failed to load - (libkern/kext) not found" message in Terminal, and "/Users/[myusername]/Library/Application Support/ROMTool/DirectHW.kext has no Info.plist file" message in Console.

It seems like the very same kext is loading if put in one place (/Applications), but not in another (~/Library).

What am I doing wrong??

Or, alternatively, how can I go backup my ROM bypassing dosdude's GUI? After all, I was able to load the kext from Terminal. I just need to know what commands to issue in order to dump the ROM next.

Thanks in advance

Sergio

I had sometime this behavior DirectHW.kext not loading or even a freeze. I do not remember with which Mac OS version. At this time what was working was to launch romtool just after booting, and it worked, don't ask me why, i don't know.

 

[Ausdauersportler]

Dear Ausdauersportler,

thank you for taking the time to answer.

Unfortunately, this is the third time you answer me with something like "you haven't read the first post, you should have looked around before posting, and anyway please find the solution by yourself as I did before you".

While actually in all of the occasions I had read the first post, I had looked around before posting, and if I decided to post, then you know?, it was just because I found no solution anywhere, and I hoped that there were people out there with more experience than me who were willing to help (otherwise, what this forum would be for?), instead of spending their time trolling newbies.

So at the end of the day your answers were empty presumption (presumption that, say, for sure I had not done my homework in advance): nothing less, nothing more. Adding no value to find a real solution for problems (or even simple doubts) that had never been tackled before.

[If I'm wrong, and you can provide a link to a post explaining exactly how to solve my specific issue with ROMtool, for instance, I will be glad to apologize of course. I was not able to find it.]

Finally, let me remark that if there is one who is posting without reading first, that seems to be you, since in all cases you overlooked important pieces of information that I posted regarding my specific situations.

Not sure whether you are doing all of this with the best intentions, or what. And maybe I was just unlucky in my interactions with you, while 99% of the time you provide brilliant solutions to everybody. But I find all of your answers to my posts to be very dysfunctional: they make people (yourself, in the first place, but of course also me and everybody else who is scrolling through the forum looking for real answers and solutions) waste a lot of time; and above all I think they deter other people from posting answers that could actually add some real value and help come up with real solutions.

So please, from now on, may I kindly ask you to ignore my posts? This is exactly what I will be doing with yours, whatever you may write in the future. Hope we can find this agreement.

Thank you

Sergio

You finally created yourself a signature, excellent!

There is an ignore button you can find on every's users icon. Select it and I will do happily the same.

Try to be sharp and precise - I have not the time to read the story of your live.

Unfortunately your questions have been asked several times before and this is not a "drop in a question and let the others to the work for you" service. This forum is to exchange experiences - this is primarily not a help desk. We are cluttered with such requests and development went away into private communications. This is not your personal fault, but you do not make it better.

This is why I ask all users to read the available docs. Making romtool work on your Mac is slightly off topic, too. We cannot provide help with every tool we use or propose to use.

P.S.:
Try to find out who wrote most off the parts of the first post right now.

P.P.S.:
You can read your rom (using romtool) several times with different chip types selected and (binary) compare the fetched files later. I never had a difference. And I ask myself why you did not come up with the same obvious solution. When changing the GPU the system will be open and you can use a CH341A.

P.P.P.S:
You may write a post about using romtool on High Sierra with nice screen shots and one could add it to the first post.

 

[vastunghia]

I had sometime this behavior DirectHW.kext not loading or even a freeze. I do not remember with which Mac OS version. At this time what was working was to launch romtool just after booting, and it worked, don't ask me why, i don't know.

Thank you Pascal, it turns out your advice was as trivial as brilliant!! 👏👏👏

I rebooted, logged in (holding Shift key during login, just to be sure), and voilà! @dosdude1 's magical tool worked out of the box!

Very strange, I'm pretty sure I had already rebooted a few times and nothing changed... anyway... solved!

I see that ROMtool asks the same question about the chip model that flashrom presented:

Guess I will cross my fingers and try all of the chip models, hoping that nothing bad can happen when in read-only. Then I will compare them somehow.

Once again, thanks a lot.

Sergio

 

[KennyW]

Ok, so I went on and tried to figure out how to dump ROM from command line, since I was able to load DirectHW.kext from Terminal (still no clue why @dosdude1 's GUI is not able to load kext... the reason being that kext cannot be loaded when put in ~/Library... )

So after successfully loading DirectHW.kext, I issued sudo ./flashrom -p internal -r ROM_dump.bin, and this is what flashrom returns:

[...]
Found Macronix flash chip "MX25L3205(A)" (4096 kB, SPI) at physical address 0xffc00000.
Found Macronix flash chip "MX25L3205D/MX25L3208D" (4096 kB, SPI) at physical address 0xffc00000.
Found Macronix flash chip "MX25L3206E" (4096 kB, SPI) at physical address 0xffc00000.
Multiple flash chip definitions match the detected chip(s): "MX25L3205(A)", "MX25L3205D/MX25L3208D", "MX25L3206E"
Please specify which chip definition to use with the -c <chipname> option.

So after looking around I found out that the safest solution would be to determine my specific chipset by opening the iMac. If this is the only possibility to keep things safe, I will do that.

I was wondering, however, if I can avoid opening my iMac -- would be a pain in the neck to do that only for this, and after all, @dosdude1 's tool does not need to do that to dump ROM, so there must be an alternative... So my questions are:

1. Is it safe to use flashrom to read (only!) ROM by just guessing the chipname option? Do I risk bricking my system? Only by trying to read ROM?
2. If the answer to 1 is 'yes, it is safe', is flashrom going to alert me in case I guessed the wrong chipset? Or is it going to produce a bin file anyway, with no possibility to understand whether everything went fine or not?

Hope I was clear in my questions.

And thanks a lot in advance!

Sergio

As I have posted before in answer to another reader here, there is no difference in choosing which flash chip to read the ROM. Just compare the output yourself for confirmation, and mine reveals no difference.

Besides, reading the ROM would not corrupt it. The ROMtool also cannot write back the Apple ROM.

The EEPROM programmer will recognise the BIOS chip automatically. There is no need for you to choose during flashing.

 

[Ausdauersportler]

As I have posted before in answer to another reader here, there is no difference ny choosing which flash chip to read the ROM. Just compare the output yourself for confirmation, and mine reveals no difference.

Besides, reading the ROM would not corrupt it. The ROMtool also cannot write back the Apple ROM.

The EEPROM programmer will recognise the BIOS chip automatically. There is no need for you to choose during flashing.

No, flashrom software will not auto detect the correct chip type on read attempts and you will have the same selection to make and specify the chip type on the command line. At least this happened to me when reading the iMac 2011 firmware to do the EG mod one month ago.

Comparing binary files:
Read the manual page for the terminal command diff. Man page?? Try man man in the terminal.

 

[Khadam]

This is odd.

Try installing OpenCore on and SD card using the attached 0.6.5per config file (I assume you have patched the system already). On boot use alt/option and choose the SD card to boot while pressing CRTL (makes it default). Another boot selector will come up showing most likely only the Big Sur installation. Boot into it and check the Big Sur.

Then make a shut down and a cold start. The OpenCore should boot and switch on the LCD by default.

This config.plist will not load any extensions already installed on your system.

Open Core works, (I have brightness control). After cold start Open Core indeed boot and switch on the LCD. Then I need to click enter to choose my BigSur drive. Essentialy, it "spares" me trouble of holding option key with added bonus of brightness control...And I need to keep my usb plugged in order for it to work.

 

[vastunghia]

Thank you Pascal, it turns out your advice was as trivial as brilliant!! 👏👏👏

I rebooted, logged in (holding Shift key during login, just to be sure), and voilà! @dosdude1 's magical tool worked out of the box!

Very strange, I'm pretty sure I had already rebooted a few times and nothing changed... anyway... solved!

I see that ROMtool asks the same question about the chip model that flashrom presented:

View attachment 1699731

Guess I will cross my fingers and try all of the chip models, hoping that nothing bad can happen when in read-only. Then I will compare them somehow.

Once again, thanks a lot.

Sergio

Ok so, just to close the matter, I dumped 3 times for each of the 3 choices in the chip selection list (obtaining 3x3=9 bin ROM dump files), and then

1. binary compared (diff'ed) one vs all the 8 others => green light, they are all the same
2. also opened one in a hex editor, just to make sure that they are not containing only zeroes => green light, they do contain some data

Thanks for the hints!

@KennyW , no, actually ROMtool does not recognize the specific chip (check my previous post with screenshot attached).

 

[Pascal Baillargeau]

Thank you Pascal, it turns out your advice was as trivial as brilliant!! 👏👏👏

I rebooted, logged in (holding Shift key during login, just to be sure), and voilà! @dosdude1 's magical tool worked out of the box!

Very strange, I'm pretty sure I had already rebooted a few times and nothing changed... anyway... solved!

I see that ROMtool asks the same question about the chip model that flashrom presented:

View attachment 1699731

Guess I will cross my fingers and try all of the chip models, hoping that nothing bad can happen when in read-only. Then I will compare them somehow.

Once again, thanks a lot.

Sergio

The best is to do maybe three dumps for each eeprom and compare them.
I see you've done it already
AFAIK, Romtool cannot flash bios on our iMac, for that we have to use a clip.

 

[Ausdauersportler]

Open Core works, (I have brightness control). After cold start Open Core indeed boot and switch on the LCD. Then I need to click enter to choose my BigSur drive. Essentialy, it "spares" me trouble of holding option key with added bonus of brightness control...And I need to keep my usb plugged in order for it to work.

I thought you use a non K610M/K1100M/K2100M NVIDIA card. Having a signature helps... You may use the NVIDIA_BigSur config file. It will fit with the installation made by the micro patcher.

Honestly: Post #1 told you to use OpenCore from the beginning!

 

[KennyW]

No, flashrom software will not auto detect the correct chip type on read attempts and you will have the same selection to make and specify the chip type on the command line. At least this happened to me when reading the iMac 2011 firmware to do the EG mod one month ago.

Comparing binary files:
Read the manual page for the terminal command diff. Man page?? Try man man in the terminal.

Sorry, that would be strange. I have no experience of using Flashrom on the Apple logic board as you do. But my using of Flashrom on GPU BIOS chips finds that it has always been able to recognize or not recognise the BIOS chip itself for reading or writing. There is no choice offered to me to select.

ROMTool is different and the version 2 gives that warning and options. That is not present in version 1.

 

[KennyW]

Ok so, just to close the matter, I dumped 3 times for each of the 3 choices in the chip selection list (obtaining 3x3=9 bin ROM dump files), and then

1. binary compared (diff'ed) one vs all the 8 others => green light, they are all the same
2. also opened one in a hex editor, just to make sure that they are not containing only zeroes => green light, they do contain some data

Thanks for the hints!

@KennyW , no, actually ROMtool does not recognize the specific chip (check my previous post with screenshot attached).

I don't mean ROMTool. It cannot recognise the brand of Apple Bootrom chip, or more accurately probably not programmed to differentiate them unless there is no signature byte of the different chips for their identity.

 

[Ausdauersportler]

Sorry, that would be strange. I have no experience of using Flashrom on the Apple logic board as you do. But my using of Flashrom on GPU BIOS chips finds that it has always been able to recognize or not recognise the BIOS chip itself for reading or writing. There is no choice offered to me to select.

ROMTool is different and the version 2 gives that warning and options. That's is not present in version 1.

I had even GPU cards coming up with this message, especially the new AMD ones. This is one from a system board ...

Spoiler: Multiple chip definitions

https://www.reddit.com/r/coreboot/comments/ianfcs

 

[KennyW]

I had even GPU cards coming up with this message, especially the new AMD ones. This is one from a system board ...

Spoiler: Multiple chip definitions

https://www.reddit.com/r/coreboot/comments/ianfcs

Always new thing to learn, even for tools I use. Thanks.

 

[KennyW]

I had even GPU cards coming up with this message, especially the new AMD ones. This is one from a system board ...

Spoiler: Multiple chip definitions

https://www.reddit.com/r/coreboot/comments/ianfcs

Ah, the Macronix MX25 series. I bought a few to change the small capacity BIOS chip on a GPU before. Didn't work. Flashrom cannot recognize them but I got no offer of choice. I looked back in the documented list for Flashrom and later bought other compatible brands.