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iM 4,1-14,4 2011 iMac Graphics Card Upgrade
- Thread starter MichaelDT
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@The_Croupier
This is Micron vram, MT51J256M32HF_1_35V. We have a vram_table that identifies this type of ram. The CRANE15 BAFFIN bios has it, as do the HP AFFLICK, AMOROHID and PEGATRON roms. As we are discovering, early BIOS initialization is more of an issue rather than vram compatibility.
This is Micron vram, MT51J256M32HF_1_35V. We have a vram_table that identifies this type of ram. The CRANE15 BAFFIN bios has it, as do the HP AFFLICK, AMOROHID and PEGATRON roms. As we are discovering, early BIOS initialization is more of an issue rather than vram compatibility.
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Great thanks for the information.
I might have a go at the HP 4170 eeprom mod that @dfranetic so precisely described.
Wondering if I can salvage the eeprom chip from a dead apple card rather than buying a new one?
I’m not sure about the type of EEPROMs on Apple GPUs, but quite frankly, why not buying a new EEPROM? (If you are located in EU, DM me and I will send you a link to my source. Moreover, it appears that your card already has RP1 on board, so you’ll have an ‘easy’ soldering job…)
Hi all,
Just wanted to share a success story.. I own a mid 2011 27" imac (12.2 model) with a nvidia 780(replaced the original 6970 in 2019) GPU. I ran Catalina for a while and had a few tries with Big Sur and OC without any luck, installation usually started but when the actual booting of the hdd started I was always greeted with a black/blank screen. Must have been something in the instructions I missed but couldn't find what it was so since Catalina always installed and worked I'd stuck with that.
Last week I opened this topic again and noticed that the opening topic had changed.... a lot, so I started reading it again with in mind that installing Big Sur might be changed a bit and I could have another go. And boy oh boy has it changed. I found the OCLP instructions! Installing Big Sur (11.4) was quick and easy using the OCLP GUI version. This morning I updated to 11.5 using the "normal" OSX update mechanism. Works like a charm!
To everyone who made this all possible a big THANK YOU VERY MUCH!!! Especially @dortania for the OpenCore Legacy Patcher v0.2.3 and the clear instructions.
Greetz,
H.
Just wanted to share a success story.. I own a mid 2011 27" imac (12.2 model) with a nvidia 780(replaced the original 6970 in 2019) GPU. I ran Catalina for a while and had a few tries with Big Sur and OC without any luck, installation usually started but when the actual booting of the hdd started I was always greeted with a black/blank screen. Must have been something in the instructions I missed but couldn't find what it was so since Catalina always installed and worked I'd stuck with that.
Last week I opened this topic again and noticed that the opening topic had changed.... a lot, so I started reading it again with in mind that installing Big Sur might be changed a bit and I could have another go. And boy oh boy has it changed. I found the OCLP instructions! Installing Big Sur (11.4) was quick and easy using the OCLP GUI version. This morning I updated to 11.5 using the "normal" OSX update mechanism. Works like a charm!
To everyone who made this all possible a big THANK YOU VERY MUCH!!! Especially @dortania for the OpenCore Legacy Patcher v0.2.3 and the clear instructions.
Greetz,
H.
Thanks for the offer but im in AU, yes indeed it looks like RP1 is there 👍
I have a lot of scrap cards so try to recycle parts when I can but your right its probably best to buy a new chip.
Gpu core have supported spi flashes list. Recommend to use supported flashes to prevent unpredictable cases. But at least you should use same brand and series, rom size and voltage
I tend to buy electronic parts new, from reputable sources. Especially as our VBIOS developers are still working hard on an appropriate VBIOS, using a new EEPROM would eliminate one (unlikely) source of failure…
Finished 2 tools that can help to analyze atom bios tables, reposition them and even patch modules positions, or switch them off.
I can share google sheet link for testing. Later will add excel sheet export, but I am afraid that it won’t work there.
I was use different builds of that sheets before I revealed java app ATOMTableResize. But this app can’t resize vgafirmware, cannot disable modules. So that’s why I have to get back to that project to make final 4150, 4170 hp vbios builds that will work on Catalina and higher!
AS EXPECTED, EXCEL NOT SUPPORT "SORT" FORMULA. HOW TO FIX IT, I DONT KNOW...
I can share google sheet link for testing. Later will add excel sheet export, but I am afraid that it won’t work there.
I was use different builds of that sheets before I revealed java app ATOMTableResize. But this app can’t resize vgafirmware, cannot disable modules. So that’s why I have to get back to that project to make final 4150, 4170 hp vbios builds that will work on Catalina and higher!
AS EXPECTED, EXCEL NOT SUPPORT "SORT" FORMULA. HOW TO FIX IT, I DONT KNOW...
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@junley4 @Nguyen Duc Hieu @nikey22
Well guys! I reread the first post several times, I'm Italian so I had to translate everything in full. Let's see if I understood and translated well.
Features of my iMac:
iMac (27-inch, Mid 2011) - 2.7 GHz Intel Core i5 - 12 GB 1067 MHz DDR3 - AMD Radeon HD 6770M 512 MB - Samsung EVO 860 PRO 512 GB SSD. High sierra 10.13.6
I hope I have understood correctly. tell me if I'm wrong before I start.
instructions to perform:
1. Boot iMac and install OpenCore Legacy Patcher latest version
(opencore-patcher-gui.app.zip)
2. mac turned off. I remove the 6770 512 mb card and install the k3100m 4gb card.
3. boot iMac by holding command + R for recovery mode and terminal boot: csrutil disable and reboot.
4. with my notebook with kali linux in ssh I connect to the mac and do the flash bios gpu.
5. reboot.
6. install package black screen for macOS High Sierra
7. restart and finish.
Right? There is something wrong?
It seems to me that regardless, by mounting the new video card the system starts working. Correct if I'm wrong.
Well guys! I reread the first post several times, I'm Italian so I had to translate everything in full. Let's see if I understood and translated well.
Features of my iMac:
iMac (27-inch, Mid 2011) - 2.7 GHz Intel Core i5 - 12 GB 1067 MHz DDR3 - AMD Radeon HD 6770M 512 MB - Samsung EVO 860 PRO 512 GB SSD. High sierra 10.13.6
I hope I have understood correctly. tell me if I'm wrong before I start.
instructions to perform:
1. Boot iMac and install OpenCore Legacy Patcher latest version
(opencore-patcher-gui.app.zip)
2. mac turned off. I remove the 6770 512 mb card and install the k3100m 4gb card.
3. boot iMac by holding command + R for recovery mode and terminal boot: csrutil disable and reboot.
4. with my notebook with kali linux in ssh I connect to the mac and do the flash bios gpu.
5. reboot.
6. install package black screen for macOS High Sierra
7. restart and finish.
Right? There is something wrong?
It seems to me that regardless, by mounting the new video card the system starts working. Correct if I'm wrong.
With vbios patching should work. Can you provide a link?
The magical first post has an answer:
AMD RX480 Works only in Late 2009 27 and Mid 2010 27 systems!
However, I compared a few high resolution photos of POSTing and non-POSTing WX7100 cards and the non-POSTing WX7100 has essentially the same layout as the non-POSTing RX480 MXM card. If you have access to high resolution photos of ’your’ specific RX480 in question, please do DM me. I can try to make a guess…
No! The first post is very clear about this. Check it out yourself.
Until now we do not have a single such patch in place. It is the same symptom as with the HP WX4150 card in the iMac12,2 - it will simply not do a successful POST.
If you have gpu for testing, we can try voltages initialization patch
No one has such a problem with Big Sur, we all use OCLP and it is the only *supported* way to install on this thread.
I do have one, and I have a iMac12,2 test system in place! Would be a great step ahead if this works!
Generally OCLP is installed after the GPU is installed.
You want Linux on the iMac, then use your MacBook to SSH into the iMac.
You forgot the step to modify your 3pipe heatsink.
I'm pretty sure the black screen package is now integrated into OCLP.
You only need OCLP if you plan to install a unsupported OSX.
As you already have the card, you can have a go and do a quick test. My guess is, this one will not POST. Are there consecutive short fan spins after the press of the power button and nothing else? (I am not yet able to explain the ‘logic’ behind my guess - I am currently trying to figure out if there is a simple hardware mod for these cards to make them POST, without having physical cards to compare - and making this a very expensive experiment/gamble.)
Yep, unfortunately that’s exactly the symptom we are getting with all non-POSTing AMD cards (or were getting for some of the non-POSTing AMD cards). Currently, there is no solution for (that) RX480 MXM card.
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