theluggage
macrumors G3
Well, if anybody has a Neo they can run System Report and find out how the USB ports are plumbed & when someone does a teardown we'll see what controller chips it has.USB 3 is 10gbps and USB 2 is 480mbps. What if they actually run on the same controller on the chip, and the USB2 port is a “daughter” to the USB3 - so if you run both maxed out, the USB2 port “steals” half a gigabit from the USB3? No one would notice outside of benchmarks. Just a completely unfounded theory.
First, I don't think I've ever seen a full pinout of any Apple Silicon chip but it's likely that they all feature some USB 2 and/or 3 interfaces and/or spare PCIe lanes (that could run USB controllers) for internal peripherals (keyboards, trackpads, WiFi etc). The "extra" USB2 most likely comes from an internal hub.
Second, USB2 and USB3 are actually quite independent, with their own electrical standards. A USB3 or USBC connector has two quite separate sets of wires for USB3 and USB2. They don't share bandwidth. A "USB3" hub effectively contains a separate, parallel USB2 hub - you can connect a USB3 device and a USB2 device and they'd both get their full bandwidth (minus the overhead of a hub).