This is how it works on PCs and thus Macs(same on the hardware level): Maybe my understanding of how Macs handle this is warped, but that doesn't explain why every device I plug in runs at 1.1 (iTunes says my iPod won't run on 1.1, an external Bluetooth stick I bought won't run on 1.1, my usb hdd runs painfully slow) and my internal Bluetooth (requires 2.0) doesn't work. When I say hubs, I'm referring to the 4 internal USB hubs (maybe I mean buses) provided by the SB chipset (iirc its Intel ICH9r). I'm not talking about the physical ports. Depending on what you plug into the port, the HCD & bus driving the port may change. What may be confusing you is that the +USB Device Tree+ abstraction visible in System Profiler may show more USB However, hubs built into Intel Macs support UHCI or EHCI as required & the OS automatically uses the appropriate HCD for the attached USB device(s). Very few hubs are upgradeable you are almost always limited to whatever USB interface standards one supports when it was made. Hubs provide electrical interface & data control for USB devices & hosts but are not themselves hosts. The OS doesn't install any HCD's on hubs (or devices attached to them). OS X (regardless of the installer interface) includes all necessary +software layer+ Host Controller Drivers (HCD's) to run the +hardware layer+ Host Controller (HC) - basically, the Mac's built-in USB hardware. USB interface standards consist of both hardware & software parts. I would like to install the AppleUSBEHCI driver for the other two hubs. When I install Mac OS X on my Macbook Pro 13" from a USB DVD drive, it installs the AppleUSBOHCI driver on two of the USB hubs (which include the external ports, and also the internal Bluetooth which doesn't run on the OHCI driver).
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