2014 Mac Mini [4th,2C,U] + RX Vega 56 @ 16Gbps-TB2>TB3 (AKiTiO Node) + macOS 10.14.6  

Computer: 

2014 CTO Mac mini 3.0GHz 2-Core i7-4578U, HD Graphics 5100, Thunderbolt 2, 16GB RAM, 512GB SSD

eGPU:

AKiTiO Node + PowerColor Red Dragon RX Vega 56 with 8GB HBM2 VRAM, 2M Apple TB2 cable, and Apple TB3 to TB2 adapter.

Monitor:

Philips Brilliance 242G5, 1080p, 144Hz, 1ms, Display Port, 2x HDMI, DVI-DL, VGA

OS:

macOS 10.14.6

Hardware setup:  

This 2014 CTO Mac mini has a 2-core i7, 16GB LPDDR3 fixed memory and dual upgradable storage.  The primary storage is a proprietary Apple-Samsung 512GB PCIe 2.0 x 2 lane blade SSD.  The secondary storage supports 2.5” SATA3 drives.  Apple discourages upgrades by using security screws in this mini.  However, kits are available from OWC and iFixit with the tools and parts needed for upgrades and repairs.  This model has two Thunderbolt 2 ports (20Gbps).  An Apple TB3 to TB2 adapter and 2 meter Apple TB2 cable were used to connect to the TB3 eGPU. 

The AKiTiO Node TB3 eGPU has a PowerColor Red Dragon RX Vega 56.  I’ve recently used this same eGPU configuration with two other builds; it’s fast and reliable.

Background: 

The purpose of this build is to find a legacy Mac that doesn’t take much space & can run my fav 32bit apps; including eyeTV iOS server; which is broken in the 64bit version.

Procedure macOS: 

This build uses purge-wrangler only because it was faster to setup than kryptonite.  I plan to upgrade later.

Always start with a backup just in case.

Next, goto the eGPU.io Software menu and select purge-wrangler.  Read the docs 1st.  This mini was easy to setup in part because it has no discrete GPU.  You have to reboot into the Restore menu (Cmd+R) to disable SIP via terminal (csrutil disable) before you can run the script.  You may also have to turn off FileVault in the System Preferences / Security & Privacy menu.

During installation, the script automatically selected all needed options for this Mac mini.  My previous builds required more interaction so this was an unexpected benefit!  Afterwards, reboot and you’re done.  I can’t emphasize enough how quickly and easily this build was competed!

Full disclosure: Other than disabling SIP, I did the install remotely from my Mac Pro.  The mini had no monitor attached except the eGPU monitor.

Operation:  

There are several advantages vs my previous build (’12 MBPro):

• Computer sleep works great!
• CPU temps are much lower (per MacFansControl)
• It’s significantly quieter especially under load!
• It takes up much less space!!
• Thunderbolt 2 (tho it’s not always faster than TB1)
• Upgradable storage (my ’18 mini fixed storage failed)
• The main storage is reasonably fast (720MB/s write, 751MB/s read)

I suspect 750MB/s may be the limit of the ’14 mini PCIe2.0.x 2 lane bus based on NVMe SSD benchmarks in my ’09 Mac Pro.  But that’s still a major boost over a SATA3 SSD and an excellent benefit of this model.  

On the downside, the i7 is only 2 cores.  It’s mostly slower than my older 4-core ‘12 MBPro TB1 eGPU.   This is apparent when you compare the results below between both builds.  Both use the identical eGPU setup.

Benchmarks:

Each result was the highest of 3 runs. 

Geekbench 4:

Unigine Valley:

Tomb Raider: 

V-Sync was set to off.  Monitor refresh set to 144Hz

Rise of the Tomb Raider: 

V-Sync was set to off.  Monitor refresh set to 144Hz

CL!ng benchmarks:

Miscellaneous: 

TB2 bandwidth:  Performance has been mostly slower on this ’14 mini build vs my previous ’12 MBPro build..  I suspect the 2-core i7 and 4MB L3 cache may be part of the reason (’12 TB1 MBPro has 4-core i7 & 8MB L3 cache).  I tested this by re-running ROTTR benchmarks on my ’12 MBPro build with the macOS Activity monitor open on the 15” display.  ROTTR used up to 685% CPU.  But the newer ’14 mini’s 2-core CPU can provide up to 400% CPU (100% per thread).  There may be other factors.  But recent games appear to benefit more from the extra CPU cores even with the slower TB1 connection to the eGPU.  At least that’s been the case with the last 2 builds. YMMV

Fan noise:  Like my ’18 i3 Mac mini before, this ’14 mini is relatively quiet.  It rarely spins up the fan and the CPU runs fairly cool.  Temps occasionally rise to 90C but are mostly well below 70C even in benchmarks with the fan idling around 1900rpm.  And when the fan does spin up, it’s much quieter than any MacBook I’ve owned!  

Conclusion:  

For casual home and light productivity use, this ’14 Mac mini + Vega 56 is a nicer build than my previous 2012 15” MacBook Pro + Vega 56.  It’s compact and quiet with more connectivity.  However, if you need the processing power of the extra CPU cores, look elsewhere.  It’s too bad 2014 was a 2-core year for the mini.  With TB2 and PCIe storage, this model would’ve been ideal with a 4-core CPU IMO.