2019 ASRock Deskmini A300 [R4K,6C,G] + RX 5500 XT @ 32Gbps-M.2 (ADT-Link R43SG) + Win10 // first SFF Desktop Ryzen 4000 Pro x4 3.0 M.2 eGPU build  

• M.2 adapter arrived, ready to mod case:

• Cable has to go through here (what and where to cut?):

• Not much clearance when assembled but should be enough (fortunately cut-out only needed for the ribbon cable, not the adapter part):

• I/O shield cut (lower right edge completely removed):

• Adapter easily connected to rear M.2 slot (clever & flat solution from ADT-Link, fits perfectly under the motherboard):

• OK, not so fast! Problems! (Cable has no flex to the sides at all, so it does not align with the new hole on my i/o shield. My bad, always measure twice before cutting. More dremeling needed. Also cable has to be protected against that metal VGA port mounting teeth thing. 4 layers of duct tape solves this though):

• I/O shield cut-out is ok now (with tiny DIY plastic cosmetic & protecting plate glued to the metal) and GPU succesfully connected:

• All set! The eGPU is hidden behind my desk with all the power bricks, cables etc. (placed on a matching DIY shelf):

• Closer look (with the Dell PSU brick attached):

And that's it! Hardware setup is no big deal if you know what to cut and how much to cut... and now we do 😛

Configuration & screenshots

After powering DELL PSU and turning A300 on, system posted just fine. The BIOS was automatically reset though (beta 3.60S). After reconfiguring all my settings (XMP, SATA mode, fan speed etc.) Windows 10 launched without problems. Half a minute later OS became somewhat unresponsive, but no system messages or errors were displayed (it was clearly something going in the background) so I did a quick reboot. After logging back to Windows all was Plug & Play, no configuration needed.

Adrenalin listed RX 5500 XT as GPU1 and Ryzen iGPU as GPU2 right away. Bus setting of the 5500 XT was reported as PCI Express 3.0 x4:

Just to be sure I disabled iGPU in device manager (GPU2 entry in Adrenaline disappeared immediately) and ran some benchmarks. I have no baseline for this CPU+GPU setup to determine performance hit of the 32 Gb/s PCIe bus vs the full supported PCIe 4.0 x8 speed (somewhere ~8%), so I can only compare results to the original 4650G iGPU setup. But this was my main goal anyway: finding out how much more GPU performance can be added to the system this way (~250$ with all new parts), compared to a costly 4750G upgrade (which adds only +15-20% iGPU performance for +100$, also ignore CPU core benefit here, as 4650G easily beats 'gaming king' Ryzen 5 3600, while GPU performance remains the weakest point of A300). So let's see my initial results! 

Benchmarking, iGPU vs eGPU comparison, DX12 vs DX11

Superposition: +255% graphics performance, 3DMark Time Spy: +286% graphics score with 5500 XT vs 4650G iGPU! NOT TOO SHABBY (© Linus Sebastian)

Shadow of the Tomb Raider benchmark: DX12, 100% GPU bound, 35 FPS vs DX11, 15% GPU bound, 49 FPS.

Gaming, FPS changes

All @ High/Ultra settings running on a 1080p 75 Hz Freesync display:

• Witcher 3: Wild Hunt | 20-25 fps → 50-60 fps
• Shadow of the Tomb Raider | 15-19 fps → 50-69 fps
• Divinity: Original Sin 2 | 28-32 fps → 100-110 fps
• Tomb Raider (2013) | 30-36 fps → 95-115 fps

These values show a major leap in gaming performance for me (from very slow to reasonably fine gameplay at maxed out graphics settings) as expected.

Temps & noise

Nothing exciting to report here, the 25 mm thick system fan keeps everything cool at ~900 rpm in the case. Sapphire PULSE has fan-stop function (no spinning fan @ idle and moderate load) and the double 100 mm fans are inaudible even at full load (obviously no problem with airflow outside the case though).

Conclusion

So I can only say that I'm fully satisfied with the price/performance ratio of this tiny little PC (not counting all the hidden parts like a 23 cm long GPU, a ~40 cm long ribbon cable coming out of the case and a giant power brick, lol). I guess this performance could have been easily matched with a mini-iTX build, but whole system would be much more expensive and bigger!