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CPU Upgrade iMac Mid 2011
- Thread starter Franzern23
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No, we are looking for:
IM121.0047.B1G
This can be part of another macOS update, like 10.8 or 10.8.1
A assume IM121.0047.B1F will simply not boot the i3770.
IM121.0047.B1G
This can be part of another macOS update, like 10.8 or 10.8.1
A assume IM121.0047.B1F will simply not boot the i3770.
Tested did not start i7 3770, still the same situation remains.
I will continue to update the efi security update 2015 to get the firmware
This is the version that was installed and installed is version 10.8.5
Updated both efi security firmware updates without getting IM121.0047.B1G
Attachments
Using the standalone firmware 2015-001 update the rom version should look like this IM121.0047.B21 ...
I doubt it will boot the i3770.
I doubt it will boot the i3770.
10.8.5 direct app store update two efi security update, respectively or got (firmware one IM121.0047.B1F) ( firmware two IM121.0047.B21 )
All tested or can not enable the i7 3770 or the same motherboard only light up the front two led lights.
I just picked up one of these. I was wondering if the 2600S i7 is a safe pick. the iMac already has 32gb of ram in it. I was going to install a SSD and then a storage drive in the optical drive caddy. Also, since this will only run HS because of the GPU, I am also wondering if linux like fedora would be OK on it.
I upgraded to a xeon 1275 and am not having sleep issues. I must be an outlier.
Could you please share some of the screenshot on "About this Mac" and "System Report - CPU part"?
I'm selecting a Xeon to buy, but haven't decided which to choose: 1270, 1275 or 1280...
Thank you.
I would go for 1270, has smaller TDP and is good to use that little extra power on dedicated GPU, 1275 has IGPU so is a no go, 1280 has a little extra juice but it has higher TDP no need to stress the PSU for that, you will not notice the difference in real life.
My 2 cents:
I think the problem might be related with the SA switch, in the "normal PC" BIOS there is a check and switch for the platform at early init (PEI) and based on that it loads the proper drivers. Maybe a socketed BIOS and lot of time and patience will bring some light.
BTW I doubt that phantom BIOS version exist, that guy who posted that screenshot most like it used a hackintosh where you can inject whatever you like in SMBIOS....
Sorry to bother you, has anyone installed the 1260L? I hope that the inside of the imac is not too hot. I have seen that this tdp is lower than the i7-2600s (65w), and the igpu is the same. Is there a problem with the sleep of the HD2000? My English is very bad
I’ve been working for some time on the reasons Ivy Bridge is not working on our iMacs, some progress has been done, but still quite a way to go. While I think it is possible, it is far from easy, so all help is welcome.
CPU microcode, while necessary, is not the only reason Ivy Bridge does not work on 2011 iMac. Intel ME8 may also be needed (still not sure about this), but I’ve already updated both on my testing and while they work fine on Sandy Bridge, Ivy Bridge still does not boot.
It is also clear that claim made 10 years ago by user @hackerwayne that bios version B1G allowed Ivy Bridge to boot was a complete scam.
Before going any further, some background info and resources I’m using on my research:
To our luck, in 2013, there was an AMI BIOS full source code leak with code from 2012, shortly after Ivy Bridge was released.
This source code can still be easily found online (google it), and helps a lot when reversing the iMac bios. There are Sandy Bridge versions of the AMI BIOS (016s) and Ivy Bridge (018s) included.
While Apple uses it's own bios, all OEM bios are somehow derived form Intel reference code, specially the SEC and PEI parts that contain the low level init code are very similar to Intel reference code, so the source code with comments is very handy to understand what's going on when reversing Apple code.
For the UEFI structure and inner working, useful resources are specs at UEFI Forum and source code at EDK II Project.
Also useful is coreboot source code as an alternative sometimes to AMI BIOS source.
For analyzing bios, I’m using UEFITool to extract parts and UEFIPatch to create patches. There is also a sister thread where UEFI patches and mods can be published.
Of interest to understand the bios init code related to CPU are the Intel® 64 and IA-32 Architectures Software Developer Manuals and for the PCH the Intel 6 Series Chipset Datasheet.
CPU microcode, while necessary, is not the only reason Ivy Bridge does not work on 2011 iMac. Intel ME8 may also be needed (still not sure about this), but I’ve already updated both on my testing and while they work fine on Sandy Bridge, Ivy Bridge still does not boot.
It is also clear that claim made 10 years ago by user @hackerwayne that bios version B1G allowed Ivy Bridge to boot was a complete scam.
Before going any further, some background info and resources I’m using on my research:
To our luck, in 2013, there was an AMI BIOS full source code leak with code from 2012, shortly after Ivy Bridge was released.
This source code can still be easily found online (google it), and helps a lot when reversing the iMac bios. There are Sandy Bridge versions of the AMI BIOS (016s) and Ivy Bridge (018s) included.
While Apple uses it's own bios, all OEM bios are somehow derived form Intel reference code, specially the SEC and PEI parts that contain the low level init code are very similar to Intel reference code, so the source code with comments is very handy to understand what's going on when reversing Apple code.
For the UEFI structure and inner working, useful resources are specs at UEFI Forum and source code at EDK II Project.
Also useful is coreboot source code as an alternative sometimes to AMI BIOS source.
For analyzing bios, I’m using UEFITool to extract parts and UEFIPatch to create patches. There is also a sister thread where UEFI patches and mods can be published.
Of interest to understand the bios init code related to CPU are the Intel® 64 and IA-32 Architectures Software Developer Manuals and for the PCH the Intel 6 Series Chipset Datasheet.
Inside AMI bios source files, there are comments with revision history. Of interest is this one:
![1655143620270.png]( "1655143620270.png")
There is no history of source code changes (we know what files changed when adding Ivy Bridge support, but not what changed inside those files). Taking a look at those files we can see a common pattern:
First, CPUs “families” are defined by their cpuid mask:
![1655143598431.png]( "1655143598431.png")
Then, usually there is CPU specific code that looks like this:
![1655143590850.png]( "1655143590850.png")
There is both CPU and PCH initialization code that requires the Ivy Bridge CPU to be recognized (and treated as a Sandy Bridge CPU). If bios is not identifying the CPU as Ivy Bridge by cpuid instruction it will not apply the Sandy Bridge specific code to it.
Of course the iMac 2011 Apple bios does not know anything about Ivy Bridge CPUID (306A0) and will skip the Sandy Bridge needed code. To fix this we need to know which bios modules are affected and patch them accordingly.
Things get worst with the memory initialization code, more on this later.
There is no history of source code changes (we know what files changed when adding Ivy Bridge support, but not what changed inside those files). Taking a look at those files we can see a common pattern:
First, CPUs “families” are defined by their cpuid mask:
Then, usually there is CPU specific code that looks like this:
There is both CPU and PCH initialization code that requires the Ivy Bridge CPU to be recognized (and treated as a Sandy Bridge CPU). If bios is not identifying the CPU as Ivy Bridge by cpuid instruction it will not apply the Sandy Bridge specific code to it.
Of course the iMac 2011 Apple bios does not know anything about Ivy Bridge CPUID (306A0) and will skip the Sandy Bridge needed code. To fix this we need to know which bios modules are affected and patch them accordingly.
Things get worst with the memory initialization code, more on this later.
I've tried to identify which UEFI modules make use of cpuid to fork code depending on cpu model. Problem is that the cpuid instruction is also used to query processor features, so it is widely used inside a lot of uefi modules.
Anyway, I've not found many modules where code is forked depending on cpu model, for most part the Apple bios assumes the cpu is Sandy Bridge and forks code depending on cpu features, that should not be a problem for Ivy Bridge which is very similar to SB regarding features.
The module I think it's causing the iMac not to boot Ivy Bridge is the MemoryInit module.
On Sandy Bridge and Ivy Bridge architectures, the Memory Controller is integrated into the CPU:
![1655207744745.png]( "1655207744745.png")
So RAM is connected straight to the CPU Integrated Memory Controller (IMC). That RAM must be recognized and initialized earliest on the PEI phase by the CPU System Agent.
Taking a look at how this is done on Intel reference code we see it is done with different code depending on CPU stepping (last digit of cpuid).
Steppings for Sandy Bridge are defined as:
![unknown.png]()
and mapped to an enum:
![unknown.png]()
using this code:
![unknown.png]()
A Sandy Bridge i7-2600 with cpuid 0x206a7 (stepping 7) will be assigned "csD2".
Back to the Apple bios, the mapping code is very similar. It lacks the debug and error features, so code will not stop execution, but a 3770 Ivy Bridge with cpuid 0x306a9 (stepping 9) will be assigned the "csUnknow" stepping. Ivy Bridge steppings are different from Sandy Bridge:
![1655290951526.png]( "1655290951526.png")
Later, ram initialization code gets very complex and undocumented, but there are many memory configuration sections that get executed conditionally depending on cpu stepping:
![unknown.png]()
So, memory initialization for Ivy Bridge will not work on the iMac 2011 Apple bios, and I think most probably is the cause of not booting.
Possible fixes would be:
- patch module to force all cpus to be recognized as Sandy Bridge stepping 7 and hope it works (no idea, since memory controller features are undocumented)
- try to replace module for that of an Ivy Bridge bios (need to have same dependencies).
Not an easy task...
As a bonus, having real Ivy Bridge MemoryInit working would allow higher ram speed (1600 MHz) and lower voltage (1.35v) ram to be used on the iMac.
Edit: Another possible source of conflict may be the PEI Function to initialize the PciExpress bus, as Ivy Bridge supports PCIe 3.0. This is pending to be researched.
Anyway, I've not found many modules where code is forked depending on cpu model, for most part the Apple bios assumes the cpu is Sandy Bridge and forks code depending on cpu features, that should not be a problem for Ivy Bridge which is very similar to SB regarding features.
The module I think it's causing the iMac not to boot Ivy Bridge is the MemoryInit module.
On Sandy Bridge and Ivy Bridge architectures, the Memory Controller is integrated into the CPU:
So RAM is connected straight to the CPU Integrated Memory Controller (IMC). That RAM must be recognized and initialized earliest on the PEI phase by the CPU System Agent.
Taking a look at how this is done on Intel reference code we see it is done with different code depending on CPU stepping (last digit of cpuid).
Steppings for Sandy Bridge are defined as:
and mapped to an enum:
using this code:
A Sandy Bridge i7-2600 with cpuid 0x206a7 (stepping 7) will be assigned "csD2".
Back to the Apple bios, the mapping code is very similar. It lacks the debug and error features, so code will not stop execution, but a 3770 Ivy Bridge with cpuid 0x306a9 (stepping 9) will be assigned the "csUnknow" stepping. Ivy Bridge steppings are different from Sandy Bridge:
Later, ram initialization code gets very complex and undocumented, but there are many memory configuration sections that get executed conditionally depending on cpu stepping:
So, memory initialization for Ivy Bridge will not work on the iMac 2011 Apple bios, and I think most probably is the cause of not booting.
Possible fixes would be:
- patch module to force all cpus to be recognized as Sandy Bridge stepping 7 and hope it works (no idea, since memory controller features are undocumented)
- try to replace module for that of an Ivy Bridge bios (need to have same dependencies).
Not an easy task...
As a bonus, having real Ivy Bridge MemoryInit working would allow higher ram speed (1600 MHz) and lower voltage (1.35v) ram to be used on the iMac.
Edit: Another possible source of conflict may be the PEI Function to initialize the PciExpress bus, as Ivy Bridge supports PCIe 3.0. This is pending to be researched.
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Hello MacRumors my greetings to your community!
I want to overclock my Imac a1311 need some help
Now i have Imac 12.1 with Intel Core i5 2400s and want to replace it with Intel Xeon 1270 v2
My EFI is 87.0.0.0.0, as i know it's a first Apple Inc EFI version before it was universal
I have several questions how to upgrade cpu in my Imac:
1. What should i do with EFI, to bring it to universal unified version, or update it for Ivi Bridge family cpu's?
2. How to simplify and secure work with EFI without any additional extra problems?
3. What is the easiest solution to make 1270 v2 work in a1311 and if it works properly after EFI reconfiguration?
Thx MacRumors for your knowledge with best wishes for happy Mac times usage!
I want to overclock my Imac a1311 need some help
Now i have Imac 12.1 with Intel Core i5 2400s and want to replace it with Intel Xeon 1270 v2
My EFI is 87.0.0.0.0, as i know it's a first Apple Inc EFI version before it was universal
I have several questions how to upgrade cpu in my Imac:
1. What should i do with EFI, to bring it to universal unified version, or update it for Ivi Bridge family cpu's?
2. How to simplify and secure work with EFI without any additional extra problems?
3. What is the easiest solution to make 1270 v2 work in a1311 and if it works properly after EFI reconfiguration?
Thx MacRumors for your knowledge with best wishes for happy Mac times usage!
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Take a look at this!
What you think is it helps to compile EFI rom file to upgrade A1311 Logic Board 820-2784-A z68 boot chip for Intel Xeon 1270 v2 Ivi Bridge CPU ?
EliteMacx86
Or maybe there is another way just update to macOS 11 and then change CPU to Ivy Bridge
What you think is it helps to compile EFI rom file to upgrade A1311 Logic Board 820-2784-A z68 boot chip for Intel Xeon 1270 v2 Ivi Bridge CPU ?
EliteMacx86
Or maybe there is another way just update to macOS 11 and then change CPU to Ivy Bridge
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I remember playing that awesome game from a floppy disk...Return Xeon E3 to vendor and just siting and playing Mach3 in DOSBox
Have a nice time to tuneup a1311 z68 boot rom it's a great Apple PC
Hopefully some day we'll be able to make Ivy Bridge 1270 v2 work on our iMacs
I am thinking there is exist a easy way to clear boot rom chip in this clever Mac systemI remember playing that awesome game from a floppy disk...
Hopefully some day we'll be able to make Ivy Bridge 1270 v2 work on our iMacs
Continued googling Mac features like How To Wipe Os From Bios Mac? ))) have a nice trip
How to mac rom bios
Has anyone convert to coreboot/tianocore? does it bypass the xeon problems ? I can help get osx running if someone tried with autoport and soic flashed etc