I recently reviewed the GMK Tech K8 Plus Mini PC, and in my initial review, I mentioned that I wanted to take a closer look at the Oculink port included on this device. Today, I’m diving into that topic, hooking up an external GPU to the Mini PC using the Oculink connection. This process involved a bit of DIY tinkering, but the goal was to see if Oculink could offer a performance boost over a Thunderbolt connection. In my latest review, you can see how it went!
Right now, Oculink solutions aren’t the most elegant. The setup I used involved an ATX power supply, an Asus 4060 GPU, and a PCI Express 4.0 Oculink adapter, and a somewhat bulky board that acts as the connection interface. It’s not pretty, but it works.
Connecting everything was straightforward, though a bit cumbersome. After slotting in the GPU, I hooked up power through an ATX supply and used an Oculink cable to link everything to the Mini PC. One crucial note about Oculink is that it’s not hot-swappable like Thunderbolt—everything has to be powered down during setup and should not be removed while powered on.
Once everything was connected and powered back on, the GPU worked right away, with the video output immediately coming from the card, similar to a desktop setup. I connected an HDMI cable directly to the GPU to output the display.
To test performance, I ran the 3DMark “Wild Life Extreme” benchmark. Compared to using Thunderbolt, Oculink offered slightly better results—about 10% higher performance. This boost is because Oculink has fewer bottlenecks, providing a more direct data path for the GPU to communicate with the rest of the system. The 3DMark Time Spy benchmark results reflected similar gains.
One fun experiment I tried was running both Thunderbolt and Oculink simultaneously. I connected a GTX 1070 through Oculink while using a 4060 GPU via Thunderbolt, and I even used the Mini PC’s onboard GPU for additional outputs. The setup worked, though it quickly turned into a complicated “tower of power” with all the cables and GPUs involved.
Overall, Oculink seems promising for those looking for an external GPU solution with minimal overhead, and it offers better performance than Thunderbolt for this use case. I am hoping we see more compact enclosures that can integrate everything into a single case similar to the many Thunderbolt PCIe boxes out there. As Thunderbolt 5 starts to roll out, it will be interesting to see how the competition between these two technologies evolves, each bringing its own set of strengths and compromises.