Framework's 10G Ethernet module exposes USB-C's complexity
Linux fares slightly worse on that laptop, but it surprised me because Framework's own port documentation for my laptop says it should support USB 3.2 Gen 2x2—at least on ports 1 and 3!The RTL8159 is bottlenecked on a many USB4 and all USB 3.2 Gen 2x1 connections. Unfortunately, that caps the bandwidth well under 8 Gbps.I tested on my Framework 12—with a slower Intel 13th Gen mobile CPU—and I found it does support USB 3.2 Gen 2x2 speeds as documented, and I should get closer to 10 Gbps.Except—at least in Linux—it didn't. The port showed up as 20000 Mbps (20 Gbps) via lsusb, but iperf3 only got me 7 Gbps.
- ▪Linux fares slightly worse on that laptop, but it surprised me because Framework's own port documentation for my laptop says it should support USB 3.2 Gen 2x2—at least on ports 1 and 3!The RTL8159 is bottlenecked on a many USB4 and all USB
- ▪Unfortunately, that caps the bandwidth well under 8 Gbps.I tested on my Framework 12—with a slower Intel 13th Gen mobile CPU—and I found it does support USB 3.2 Gen 2x2 speeds as documented, and I should get closer to 10 Gbps.Except—at leas
- ▪The port showed up as 20000 Mbps (20 Gbps) via lsusb, but iperf3 only got me 7 Gbps.
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Framework's 10G Ethernet module exposes USB-C's complexityJun 24, 2026I've been following WisdPi's development of various 5 Gbps and 10 Gbps Ethernet adapters for the past couple years.They use newer Realtek Ethernet chips, which sometimes have performance quirks—most frequently encountered under Linux.In today's video, I tested the new WisdPi 10G Ethernet Expansion Card for Framework computers. It fits in any available Framework Expansion slot—even on the Framework Desktop.But Expansion Cards use USB-C for their connection to the mainboard—and therein lies the rub....embed-container{position:relative;padding-bottom:56.25%;height:0;overflow:hidden;max-width:100%}.embed-container iframe,.embed-container object,.embed-container embed{position:absolute;top:0;left:0;width:100%;height:100%}The…
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