System specs
27" iMac late 2015 17,1, (thunderbolt 2)
3.2 GHz Quad-Core Intel Core i5
32GB Ram
1 TB Fusion
AMD Radeon R9 M390 2GB
MacOS Catalina 10.15.2
eGPU hardware
XFX AMD Radeon VII
Apple TB3->TB2 adapter + OWC 0.5m TB2 -> TB2 cable
Display port cable to Samsung UE590 28" 4k monitor
Installation steps
Followed the steps outlined here: https://github.com/mayankk2308/purge-wrangler/blob/master/README.md
For disabling the SIP, I left out the "$" in the instructions linked above. This maybe code speak that I was to ignore regardless.
Benchmarks
I bought this egpu purely for 4k video work in davinci resolve. I am curious about gaming, so I've included a few gaming benchmarks. I've yet to really get into Davinci Resolve with this setup, but I will update this post once I've done so.
Geekbench 5 scores. This a massive difference between Metal and OpenCL. With the 5700xt and RX580, there wasn't such a large gap between Metal and OpenCL.
Geekbench 5 OpenCL with internal display accelerated:
The following benchmarks are with the external display accelerated:
Comments
I've previously tested the 5700XT (returned it) and the Sapphire Pulse RX580. The 580 is a solid card and outperformed the 5700XT in all but the Unigine tests. The VII just went on sale and I really wanted a 16gb card as I work with 4k media. So far in all tests it's blowing the doors off both of those cards. Hopefully in Davinci Resolve 16 I'll really see a bump. Yes, I have the fan issue when in sleep and turned off. I don't find it annoying as I've disabled sleep mode and I rarely turn off the machine but whenever I do I'll just turn off the Razer Core X.
For comparisons sake, here is my 5700XT build: https://egpu.io/forums/builds/2015-27-imac-r9-m390-6th4c-xfx-5700-xt-16gbps-tb2tb3-razer-core-x-macos-10-15-1-koncept_zero/
Here is my RX580 build: https://egpu.io/forums/builds/2015-imac-171-6th-4c-i5-skylake-amd-rx-580-20-gbps-tb2-razer-core-x-macos-catalina-10-15-1-for-davinci-resolve-tested-5700-xt/
I've found that if I disconnect the egpu from the menu at the top of the OS, I can sleep the mac. Then I just turn off the egpu. When I wake up the mac, I then flip the switch to the egpu and the 2nd screen turns on. Simple as that. No fan issue.
Davinci Resolve 16 is still not good with my setup. Even after making optimized media and render cache. It's got to be the tb2, CPU, and lack of pcie ssd that's holding it back as the egpu isn't getting much use.
For gaming, this setup is great, even in Mac Os.
@koncept_zero Which internal drive does your 2015 27" iMac have? If it's a Fusion setup, the internal PCIe drive slot can be used. It's actually PCIe 3.0 so you can take advantage of the highest performing NVMe drives available. The required component is Sintech NGFF M.2 nVME SSD Adapter.
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@koncept_zero Which internal drive does your 2015 27" iMac have? If it's a Fusion setup, the internal PCIe drive slot can be used. It's actually PCIe 3.0 so you can take advantage of the highest performing NVMe drives available. The required component is Sintech NGFF M.2 nVME SSD Adapter.
Yes it's the 1tb Fusion. I think I'm goign with a mac mini setup. The 2015 is just not worth spending money on outside of the egpu imo.
I have the same iMac and am looking to get a more powerful graphics card - via an eGPU - for 3D (Blender). I'm worried about disabling the SIP. Doesn't that leave your computer open to all kinds of nasty Malware? Do you have a workaround for it? Thank you
iMac (Retina 5K, 27-inch, Late 2015), 3.2 GHz Quad-Core Intel Core i5, 32 GB 1867 MHz DDR3, AMD Radeon R9 M390 2 GB, 2TB internal SSD (iFixit upgrade bundle)
@koncept_zero, Even with the cap at 16gbs did hooking a external monitor help with bandwidth so You can use the egpu and the graphics card in it
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
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@miah_adib, you can search the build guides for builds that use Thunderbolt 2. I think they perform well compared to Thunderbolt 3 builds with the display connected to the eGPU.
https://egpu.io/best-external-graphics-card-builds/
@joevt, I HAVE USB-C 3.1 though
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
.I have the same iMac and am looking to get a more powerful graphics card - via an eGPU - for 3D (Blender). I'm worried about disabling the SIP. Doesn't that leave your computer open to all kinds of nasty Malware? Do you have a workaround for it? Thank you
I had no issues with SIP disabled. I sold this computer a couple months ago but I'm not sure if you can reenable it after the fact. Run an anti-virus software if you're concerned.
@koncept_zero, Even with the cap at 16gbs did hooking a external monitor help with bandwidth so You can use the egpu and the graphics card in it
I'm not sure what you're asking but I only used this setup with an external monitor and had decent results. I sold this computer a couple months ago and got a 2018 Mac Mini. I've found the biggest bottleneck for my use was CPU not USB port (TB3 vs TB2.) When I upgraded to a mac-mini and paired it with my Radeon VII, I saw little improvement with pure graphics performance.