WisdPi's 10G module for Framework laptops can't escape USB-C bandwidth chaos

Framework’s expansion slots all route through USB-C, and that connector’s tangle of overlapping standards is what undermines WisdPi’s new $99 10G Ethernet card. Its Realtek RTL8159 controller needs USB 3.2 Gen 2x2 (20 Gbps) to reach full speed, but most USB4 and all Gen 2x1 ports throttle it below 8 Gbps. Even on ports that advertise Gen 2x2, Jeff Geerling found the built-in drivers in both Linux and Windows topped out around 7 Gbps; only after installing Realtek’s Windows driver did he hit the card’s real-world ceiling of about 9.4 Gbps. The Linux story was worse — Realtek’s driver wouldn’t compile against Ubuntu 26.04’s newer kernel.

Heat is the second strike. Under sustained load the module’s plastic surface approached 70°C — within IEC 62368-1 safety limits only if skin contact stays under 10 seconds, which is an awkward bar for a device people use on their laps. The card also juts a couple centimeters past the chassis, so it won’t survive a snug sleeve or bag.

Geerling’s takeaway is pragmatic: most people are better served by Framework’s $40 2.5G card, and the 10G option only makes sense for those who need the speed and refuse an external dongle. The episode is less a product flaw than a case study in how USB-C’s spec sprawl makes predicting real bandwidth a guessing game even when the port labels say otherwise.