iMac USB 3.0 Question

[jbg232]

I'm purchasing a new iMac and am worried about the wired keyboard. I am worried that the USB 2 interface will slow down the USB bridge. I have multiple USB 3 hard drives that I need to run at USB 3 speeds. From my understanding, the USB port speed is dependent on the 1st device the computer sees as apple states in their FAQ:

Q: How do I get the best performance from the USB 3 ports?
A: The first device you plug in will configure the port, so always connect USB 3 capable hubs or devices first.

Thus, if I have both my USB 3 hard drives and my USB 2 keyboard plugged in, is there any possibility that the drives will actually run at USB 2 speed?

Anyone have any experience or answers to this question?

 

[macthefork]

They're talking about each of the four Ports. So, your USB 3 Drives will run at USB 3 speeds if they are the only thing plugged into a port. If you have a USB 2 keyboard plugged into one port and the USB 3 drive plugged into a second port, the USB 3 device will run at Usb 3 speeds.

If you use a USB 3 hub, then this is where the USB 3 devices have to be plugged in first to get the proper speed on that port that the hub is plugged into.

 

[jbg232]

They're talking about each of the four Ports. So, your USB 3 Drives will run at USB 3 speeds if they are the only thing plugged into a port. If you have a USB 2 keyboard plugged into one port and the USB 3 drive plugged into a second port, the USB 3 device will run at Usb 3 speeds.

If you use a USB 3 hub, then this is where the USB 3 devices have to be plugged in first to get the proper speed on that port that the hub is plugged into.

So each port acts completely independently? I ask because usually 2 ports share the same bus internally at the motherboard level.

 

[macthefork]

On our Late 2012 iMac, I have one USB 2 hub plugged into one port (this I use for my older USB peripherals including the keyboard). The other three ports have USB 3 devices connected. All three USB 3 devices work at their proper speed.

 

[thedeske]

On our Late 2012 iMac, I have one USB 2 hub plugged into one port (this I use for my older USB peripherals including the keyboard). The other three ports have USB 3 devices connected. All three USB 3 devices work at their proper speed.

Same for me - use a hub for wired key and mouse, printer - High speed USB drives attached to other ports. No problems

 

[yjchua95]

So each port acts completely independently? I ask because usually 2 ports share the same bus internally at the motherboard level.

Nope, each port is completely independent of each other.