The manufacturer of the OneXFly has announced a new crowdfunding project to produce a new add-on for its handheld gaming PC. It’s going to be an external GPU but one with an extra feature: one M.2 slot for a SSD.

External graphics cards (eGPUs) for handhelds aren’t a completely new thing, as the Asus ROG Ally supports the company’s latest ROG XG Mobile. That houses a 150W GeForce RTX 4090 Laptop chip and also acts as an I/O expansion unit, with four USB Gen 3.2 ports, an SD card slot, and an ethernet socket.

One-Netbook, the maker of the original OneXPlayer, is aiming to do the same for its OneXFly handheld. At the moment, the group is crowdfunding the project but if it’s successful, then the OneXGPU will serve a similar function as the XG Mobile, though with a few significant differences.

Firstly, the GPU inside will be a Radeon RX 7600M XT, which is exactly the same as the desktop Radeon RX 7600 graphics card but with a lower power limit (120W vs 165W), so it shouldn’t be too dissimilar, in terms of performance. That’s assuming the OneXGPU doesn’t reduce the power cap further, of course.

The project isn’t replete with technical details, unfortunately, so it’s not entirely clear how the unit will connect to other devices. The project’s page states that the OneXGPU will be equipped with two HDMI and two DisplayPort outputs, two USB Type-A and one USB Type-C ports, plus a LAN and OCuLink connection.

Given that the OneXFly has two USB4 Type-C ports and this device is used in the promotional images for the eGPU unit, I strongly suspect that the one on the OneXGPU will be the same version. OCuLink is a type of PCI Express connection system, though it doesn’t supply any power, unlike the PCIe slots in your desktop PC. That doesn’t matter for this device as it’s powered by an external DC source.

The reason as to why the connection system is so important here is that the main feature being promoted by One-Netbook is the integrated M.2 slot for NVMe SSDs, up to a 2280 size format. Now you might wonder how a single USB4 connection can handle GPU and SSD traffic together. Well, that seems to be explained by the promotional video on the project site.

For a couple of seconds, the animation shows an SSD being inserted into the slot, with a PCIe 2.0 label on the drive. That could be a typo but if the unit’s USB Type-C port is USB4 Gen 4 then it could possibly support up to 80Gbps when used in the so-called Tunneled PCIe mode.

Most SSDs use four PCIe lanes to transmit data and the Radeon RX 7600M XT uses eight of them. If that’s the case here and the SSD runs at PCIe 2.0 and the GPU at PCIe 3.0, despite supporting 4.0, then there still wouldn’t be enough bandwidth from a USB4 Gen 4 port. Only just, mind.

But an SSD running on a four lane PCIe 2.0 interface would be somewhat bottlenecked by the connection, as you’d get less than 2,000MB/s of bandwidth. Even slow PCIe 3.0 SSDs will exceed that figure, so if the detail in the video is correct, then it’s not particularly encouraging.

A possible way around that problem would be to use the OCuLink just for the GPU or SSD, but the host device (laptop or handheld PC) needs to have such a port, and it’s not a very common sight.

One-Netbook’s solution might be that the GPU and SSD can’t use the PCIe connection at the same time but that would mean you’d never want to play any games directly installed on the drive.

Overall, the OneXGPU does look very neat and could work with devices other than One-Netbook’s own. The images suggest it will be quite compact and the use of a low power GPU means that it shouldn’t require a bulky power supply to run it.

The Radeon RX 7600M XT offers a lot more performance than the integrated GPUs found in all of the AMD-powered handheld devices, though it won’t turn them into 4K gaming beasts.

The integrated M.2 slot could prove to be a cool feature but the lack of information about the OneXGPU’s connection system leaves a lot of questions unanswered. If you’re trying to raise funds via crowdsourcing, letting potential customers know exactly what they’re paying for is a must.

Over to you, One-Netbook.