EXP GDC TH3P4 Lite Thunderbolt GPU Dock Review (2024)

UPDATE: Since the introduction of this eGPU dock, EXP GDC have released two more versions of the TH3P4 which can be found here. The original TH3P4 reviewed in this post is now commonly branded the TH3P4 Lite and includes a simple GPU bracket.

Introduction

Outside of buying a second hand mainstream eGPU, low cost third-party options for the Thunderbolt 3 interface have been relatively limited. TheADT-Link R43SG-TB3was the first readily available and affordable Thunderbolt 3 external graphics enclosure, followed more recently by theWikingoo eGPU.

Now there is a third option. Designed by CloudHero and marketed under theEXP GDCbrand, best known for mPCIe/M.2/Expresscard eGPU adapters. This being their first Thunderbolt 3/4 eGPU adapter – theEXP GDC TH3P4 Thunderbolt GPU Dock.

At the time of this review the total cost including delivery wasUS$126making it the lowest cost Thunderbolt eGPU available.

Design and Features

TheTH3P4is a very small and primitive device. Measuring 153mm x 103mm x 23mm and consisting essentially of a single printed circuit board with a 3D printed plastic enclosure, it lacks any kind of bracketing or bracing for GPU security.

It uses a JHL7440 Thunderbolt 3 Controller Module which is attached to the PCB by what looks like two M.2 connections and has two Thunderbolt 3 USB-C Ports. The Thunderbolt Module looks extremely similar to the one used in theAcasis TBU412 NVME Enclosure.

The PCIe slot is full length and rotated 90 degrees, enabling the installed GPU to lay flat along the body of the enclosure.

Power is delivered through either a standard 5.5mm x 2.1/2.5mm DC Barrel Interface or PCIe 8 Pin ATX PSU input. An ATX 24Pin to 8Pin Adaptor is included. The TH3P4 has two Thunderbolt USB-C Ports and supports Thunderbolt Daisy Chaining. This is a rare and interesting feature to include in an eGPU. The port closest to the DC input is the primary connection and supports power delivery to the host device, however I am unsure what the actual delivered wattage is. For testing, I used a generic 12V 10A DC Power Supply.

Setup and Installation

Setting up and installing theTH3P4is very simple. First, install your GPU in the PCIe slot and then attach your preferred power source. Then attach the eGPU to the host device via the Thunderbolt Port located closest to the DC input. Windows will recognize the device and begin installing drivers required for the installed graphics card.Once Windows has installed the drivers, the device is essentially ready to use. However, I would recommend installing the latest drivers for your installed GPU.

Performance

I tested theTH3P4with a GigabyteGTX 1650OC Low Profile. This is one of the most powerful cards available that does not require additional power delivery beyond the PCIe interface. It also highlights the portability of using an external DC power supply.

TheTH3P4uses the JHL7440 Thunderbolt Controller, which has seen better bandwidth than older controllers and has on occasion resulted in slightly better performance. InCuda-Z, I was getting around ~2400Mbps Device to Host and ~3000Mbps Host to Device.

Unigine Heaven Ultra Settings Internal Screen:

Usability

One of the most interesting features of theTH3P4is the inclusion of a second Thunderbolt Port, capable of daisy-chaining. This enables the user to attach a GPU as the first link in the chain, and then attach additional Thunderbolt devices downstream of the eGPU. I had a mixed experience with this. Attempting to attach a native USB flash-drive directly to the second Thunderbolt port resulted in no device being detected by Windows. However, I was able to daisy-chain anAcasis TBU412Thunderbolt NVME Enclosure, a Samsung Portable USB SSD and aWikingoo eGPUEnclosure without any apparent issues.

An issue I encountered was theTH3P4reporting different charging levels to Windows. When hot-plugged, it appeared to charge my ThinkPad L13 Gen 2 without an issue, even under load. However, if I shutdown or restarted with theTH3P4connected, both BIOS and Windows would report slow charging from the device. The included instruction manual stated that “if charging is required, do not connect Thunderbolt Port 2”, however I was able to maintain normal charging with a daisy chained device. All-in-all, the power delivery is a bit of a mystery in this device.

Finally, the primary downside of theTH3P4 is the physical design. The complete lack of GPU bracket support makes the device an awkward platform. However, it appears that not long after this review was published, a version of the TH3P4 with a very simple metal enclosure that the GPU can be mounted to was made available:

Conclusion

TheTH3P4 has some excellent features. It is extremely small, enables the use of cheap and portable DC power supplies and contains the elusive ability to daisy-chain Thunderbolt devices, with the eGPU itself being the first device in the chain. The inclusion of the superior JHL7440 Thunderbolt Controller was a welcome surprise in such an affordable device, and with the now optional metal bracket, it allows for a compact and expandable eGPU option.

UPDATE: Since the introduction of this eGPU dock, EXP GDC have released two more versions of the TH3P4 which can be found here. The original TH3P4 reviewed in this post is now commonly branded the TH3P4 Lite and includes a simple GPU bracket.