Hi, I am a happy owner of an iMac of which last year I upgraded the CPU, RAM and SSD. Unfortunately, a few days ago, more precisely after resetting the NVRAM and while using Disk Utility, some artifacts appeared on the screen, but then immediately disappeared, until they reappeared and made the computer unusable.
I know for sure that is not the LCD panel because the artifacts are also visible in a snapshot, as you can see when it started:
The situation with my iMac is currently as follows:
2021 Intel TB4 | i5-11400F 2,6 GHz - 16GB 3200 MHz DDR4 - NVMe 250 GB PCIe 4.0 - RX 570 4GB GDDR5
2019 MacBook Air (MacBookAir8,2, i5 1,6 GHz, 8 GB) + RX 570 @ R43SG-TB3
2010 21.5-inch iMac (Custom Build, i5 3,2 GHz, 12 GB, AMD FirePro M4000 1GB GDDR5)
@francesco_ripa, Since you're comfortable doing SSD upgrades, I'd recommend taking the GPU card out and reflow it. If you don't have a heat gun, you can use a oven to achieve a similar effect.
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2021 Gigabyte Z590i Vision D [11th,6C] + RTX 3060 Ti @ 32Gbps-TB4 (Gigabyte Gaming Box) + Win11 [build link]
Hello and thank you for the suggestion, it seems like a very good solution that I honestly hadn't thought of.
In the meantime, I managed to boot the system by following these steps:
- Reset the SMC.
- Reset VRAM.
- Boot into Internet Recovery, hold keys during boot until you see the Apple logo: Shift + Command + R
- In the upper menu select "Utilities" and then "Terminal"
- In Terminal disable SIP, type and hit return: csrutil disable
- Type and hit return: reboot
- Boot into Internet Recovery (again)
- In the upper menu select "Utilities" and then "Terminal"
- Disable AMD GPU, type and hit return: nvram fa4ce28d-b62f-4c99-9cc3-6815686e30f9:gpu-power-prefs=%01%00%00%00
- Enable Verbose Mode, type and hit return: nvram boot-args="-v"
- Type and hit return: reboot
- Boot into Single User, hold keys during boot: Command + S
- Mount Root Drive, type and hit return: /bin/mount -uw /
- Make Directory for bad AMD Extension, type and hit return: mkdir -p /System/Library/Ext-Off
- Move the AMD Extension, type and hit return: mv /System/Library/Extensions/AMDRadeonX3000.kext /System/Library/Ext-Off/
- Update the change, type and hit return: touch /System/Library/Extensions/
- Type and hit return: reboot
Here's the result:
I found on eBay a AMD FirePro M5100 for 60$, since the dGPU is 11 years old it seems far too tempting to leave the same graphics card, plus I would have Metal and macOS Monterey.
2021 Intel TB4 | i5-11400F 2,6 GHz - 16GB 3200 MHz DDR4 - NVMe 250 GB PCIe 4.0 - RX 570 4GB GDDR5
2019 MacBook Air (MacBookAir8,2, i5 1,6 GHz, 8 GB) + RX 570 @ R43SG-TB3
2010 21.5-inch iMac (Custom Build, i5 3,2 GHz, 12 GB, AMD FirePro M4000 1GB GDDR5)
@francesco_ripa, I don't recommend buying replacement dGPU for your iMac. All of them are in similar shape and will fail soon. At least with baking the GPU yourself, you can always redo it when it starts to fail again.
LinkedIn | Youtube | Instagram
• external graphics card builds
• best laptops for external GPU
• eGPU enclosure buyer's guide
2021 Gigabyte Z590i Vision D [11th,6C] + RTX 3060 Ti @ 32Gbps-TB4 (Gigabyte Gaming Box) + Win11 [build link]