Newbie looking for build: iMac (late 2012) with OS Catalina 10.15.7 and Thunderb...
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Newbie looking for build: iMac (late 2012) with OS Catalina 10.15.7 and Thunderbolt 1 port  


Aaron Infante-Levy
New Member
Joined: 2 months ago

Hey everyone! So happy to have found this community. Thanks to Mac_editor and those of you who've been selflessly providing support for users of older Macs. I am a total newbie to this, and probably behind most of you when it comes to computer literacy. I'm looking to improve performance with graphics-intensive softwares like Maya and Adobe CS, and - if I'm lucky - run some newer games like Baldur's Gate 3 and Cyberpunk 2077.

I couldn't find the exact build for my machine, so I'm hoping some of you might be able to point me towards something that's "close enough"?


My machine is a late 2012 iMac (27") with 2 Thunderbolt #1 ports

OS Catalina 10.15.7

Processor: 3.2 GHz Quad-Core Intel Core i5

Memory: 16 GB 1600 MHz DDR3

Graphics: NVIDIA GeForce GTX 675MX 1 GB (which is a discrete graphics card)


My understanding is that finding a build is the safest most assured way for a newbie like me to install an eGPU. I found 2 builds for iMacs using Mac OS 10.5:

Both are for 2013 iMacs, with one connecting to an AMD RX 580 and the other connecting to an AMD Radeon VII


Disclaimer: I'm a bit overwhelmed as researching, purchasing, and setting up an eGPU is completely new to me. I was reading a 2018 MacWorld article which seemed to indicate that only Blackmagic Design eGPUs (either Radeon Pro 580 or Radeon RXVega 56) are compatible with my late 2012 iMac, but I honestly don't know if that's accurate or not. I'm also puzzled because that article said I'd need both a USB-C to Thunderbolt Adaptor and a Thunderbolt 2 to 2 Cable...but I have Thunderbolt 1 ports, not Thunderbolt 2. As you can tell, I'm pretty out of my depth and appreciate any pointing to clear guides/resources you can offer.

This topic was modified 2 months ago

To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.


Noble Member
Joined: 3 years ago

@aaron_infante-levy, no eGPU is compatible with Thunderbolt 1 or Thunderbolt 2 Macs. There is a workaround to make them work however.

Thunderbolt 1 and Thunderbolt 2 cables are the same. The Thunderbolt 3 to Thunderbolt 2 Adapter also work with Thunderbolt 1 devices.

I think those builds are close enough to your setup for you to follow.

The builds guide search feature can use regular expressions for searching. Each expression is separated by a space. For example:

Mac 201[2-3] GTX?[67]\d+M macOS 10\.1[3-5]

This one searches for Macs with model year 2012 or 2013, that have a dGPU that is GT or GTX, 700 or 600 series, M for mobile, running Mac OS 10.13, 10.14, or 10.15.


Mac mini (2018), Mac Pro (Early 2008), MacBook Pro (Retina, 15-inch, Mid 2015), GA-Z170X-Gaming 7, Sapphire Pulse Radeon RX 580 8GB GDDR5, Sonnet Echo Express III-D, Trebleet Thunderbolt 3 to NVMe M.2 case