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USB Ethernet alternative to RTL8153 for Mac Big Sur and M1


Sometimes WiFi just won't cut it. Luckily gigabit Ethernet has been around for ages with switches and cables costing very little and gigabit Ethernet adapters being integrated in just about all types of computers - except Apple laptops.

So, when work calls for Ethernet and you have an Apple laptop you plug in a USB to Ethernet adapter. They come in all shapes and sizes and some are cheap while others are not. But they are all powered by the same Realtek RTL 8153 chip.

MacOS come with an Apple made driver - but it is buggy (AppleUserECM.dext). There are reports it causes high CPU load and many - including me - have noticed it crashes under high workloads such as when moving large files between the computer and a NAS. And moving large files is really the reason you would like to use Ethernet instead of WiFi in the first place

Realtek does offer their own driver but so far (March 2021) there is no driver for Big Sur and the new M1 CPU.

Actually, the RTL8153 is part of a family of USB to Ethernet chipsets:

  • RTL8153 and RTL8153B: USB3 to Ethernet 10/100/1000 Mbps

  • RTL8154 and RTL8154B: USB2 to Ethernet 10/100/1000 Mbps

  • RTL8156 and RTL8156B: USB3 to Ethernet 10/100/1000/2500 Mbps

I have been unable to find any information about what the difference between the B and non-B versions are.

The version using a USB2 bus is not appealing since it would greatly limit the maximum speed and I have not seen any products using it. I have, however, seen ONE product with the RTL8156B chip: a cheap Chinese no-name dongle. Even though I don't have a 2500 Gbps switch I thought I'd try it out just in case Apple's RTL815x driver works better with this chip.

It does.

I got the dongle, plugged it into my monitor's USB hub and it connects at 1000 Mbps (since that is the speed my switch is running at) just like my old adapter. When I copied a 45 GB file back and forth between my MacBook Air M1 with Big Sur and my NAS it worked without problems.

Some related resources: