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CPU Upgrade iMac Mid 2011
- Thread starter Franzern23
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Yes, I've been researching and testing this for some months now.
It's not just updating microcode or ME version, that's the "easy" part, but main problem seems to be the FSB and memory controller initialization, which are done straight from the CPU and different between architectures and cpu stepping.
Of course all help is very welcome, I'll publish here my findings on a few days.
Today I upgraded my iMac 2011 27" i5 2500s with i7 2600 2700k and it works fine.
I got the machine system has been corrupted can not enter the system, installed the SSD with windows 10 system inserted into the boot to detect the bootrom version IM121.88Z.0047.B1D.111017110
Check the bios version for the original version of 2011.10.17 system should also be the most original macOS 10.6.8 version.
Replaced the i7 3700 boot normal power on the motherboard light front two LEDs, did not light up the screen is a pity, I talk about installing macOS version 10.7.2 to test whether the normal recognition of i7 3770.
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I got the machine system has been corrupted can not enter the system, installed the SSD with windows 10 system inserted into the boot to detect the bootrom version IM121.88Z.0047.B1D.111017110
Check the bios version for the original version of 2011.10.17 system should also be the most original macOS 10.6.8 version.
Replaced the i7 3700 boot normal power on the motherboard light front two LEDs, did not light up the screen is a pity, I talk about installing macOS version 10.7.2 to test whether the normal recognition of i7 3770.
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Downloaded the certificate expired can not unzip the production of installation U disk installation, there is no image file can be made to install the U disk to install it?
You may reset your system date and time (before Oct 24th 2019) to recover from expired certificates....
First of all: Do not upgrade! You may update the firmware and loose the ability to boot the i7 3770.
Just used the oldest macOS version you can get!
Second: Dump the current firmware and save it.
--
The internet archive has most old images, like this:
macOS Lion 10.7
macOS Snow Leopard 10.6.7
Use an 8GB FAT32 USB and Balena etcher to create an USB installer.
Just used the oldest macOS version you can get!
Second: Dump the current firmware and save it.
--
The internet archive has most old images, like this:
macOS Lion 10.7
macOS Snow Leopard 10.6.7
Use an 8GB FAT32 USB and Balena etcher to create an USB installer.
Using the Black Apple model has nvme SSD 1T SSD USB3.1 interface plug USB3.1 interface U disk production and installation read and write faster.
Modify the system time to open the certificate or the past can not decompress the production and installation of U disk.
Installed the 10.6.7 system through the original CD-ROM boot, now how to upgrade to 10.7.2 system?
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Yes I'm pretty sure it was the i7 3770 motherboard that lit up the front two LEDs screen without any display, I replaced the i5 2500s now it's the i7 2600 installed with the original 10.6.7.
i7 2600 i7 2700k i7 3770 i7 4790 I have it all!
So please do not update the macOS!
First save the firmware! Boot from an external USB disk with High Sierra installed and use the Romtool to save it. You need to disable SIP from the recovery in advance.
Tried a variety of download tools are too slow only Google Chrome can download but too slow only poor 200kb / s or so
The normal speed of my broadband is 50mb/s, and this speed is a torture.
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10.6.7 system under the direct installation upgrade error installation failure
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Who can provide
Mac OS X Lion 10.7.2 (11C74)
Mac OS X Lion 10.7 (11A511)
A link to a faster download address for the original image
These two addresses are too slow to try a variety of download tools are interrupted on the way. Only a poor 150-200kb/s, my broadband normal modest is 50mb/s speed.
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Mac OS X Lion 10.7.2 (11C74)
Mac OS X Lion 10.7.2 (11C74) : Apple Inc. : Free Download, Borrow, and Streaming : Internet Archive
The 10.7.2 update is recommended for all OS X Lion users and includes general operating system fixes that improve the stability, compatibility, and security of...
archive.org
Mac OS X Lion 10.7 (11A511) (Retail DVD) : Apple Inc. : Free Download, Borrow, and Streaming : Internet Archive
General requirements Mac computer with an Intel Core 2 Duo, Core i3, Core i5, Core i7, or Xeon processor2GB of memoryOS X v10.6.6 or later...
archive.org
These two addresses are too slow to try a variety of download tools are interrupted on the way. Only a poor 150-200kb/s, my broadband normal modest is 50mb/s speed.
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All the three files are the same, there is a simple terminal command called diff to check this:
Code:
% diff file1 file2
%
Code:
% diff file1 file2
binary files file1 and file2 differ
%Installed 10.7.2 system respectively Checked bootrom firmware did not change to keep IM121.0047.B1D
10.13.6 changed the bootrom firmware result is still the same.
Both systems are the same result replacing the i7 3770 boot only the two LEDs on the front of the motherboard
I guess the bootrom firmware is included in the image installation file and the bootrom is upgraded when the system is installed and upgraded.
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10.13.6 changed the bootrom firmware result is still the same.
Both systems are the same result replacing the i7 3770 boot only the two LEDs on the front of the motherboard
I guess the bootrom firmware is included in the image installation file and the bootrom is upgraded when the system is installed and upgraded.
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Yes, the firmware updates are included within the macOS updates.
We are looking for a way to find the mysterious version IM121.0047.B1G (which is slightly newer than the IM212.0047.B1D you found). I guess one has to find this macOS 10.8.1 update to get it from the B1G.
But I have not much hope and believe the post made back in 2012 is a complete scam.
Edit:
Apple published in 2021 the Mountain Lion 10.8 installer...maybe an update from the original 10.6.x DVD version you had will bring you to this B1G firmware level? You would have to flash back the old firmware using a CH341A clip using flashrom.
We are looking for a way to find the mysterious version IM121.0047.B1G (which is slightly newer than the IM212.0047.B1D you found). I guess one has to find this macOS 10.8.1 update to get it from the B1G.
But I have not much hope and believe the post made back in 2012 is a complete scam.
Edit:
Apple published in 2021 the Mountain Lion 10.8 installer...maybe an update from the original 10.6.x DVD version you had will bring you to this B1G firmware level? You would have to flash back the old firmware using a CH341A clip using flashrom.
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Installed 10.7.2 again with a USB stick, then the programmer refreshed the backup IM212.0047.B1D version.
The clip is very bad to operate total time spent close to five minutes, ROM capacity is relatively large this is a long process.
I will install and test this version feedback results.
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Unfortunately it is not sure which update you need to apply to get to this famous IM121.0047.B1G.
Hope you are lucky with that. Yes, flashing the iMac firmware is a pain
BTW: Recently I got a Pomona clip, this one can be used without holding it the whole 6 minutes.
Hope you are lucky with that. Yes, flashing the iMac firmware is a pain
BTW: Recently I got a Pomona clip, this one can be used without holding it the whole 6 minutes.
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Installed this version bootrom firmware did not change no or have to update
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