Hello. On the new 17" MBP, there are three USB ports on the left. Are there any differences? I recall reading somewhere that only one of the ports can be used to power a device that requires more power (e.g. portable hard drive that draws power from the laptop). The reason I am asking is that I am using a special software that requires the users to plug in the USB hardware key. I plugged it in the port closer to the palm rest area. It did not work. Then, I plugged it to the USB port near Magsafe connector. It works. I wonder if the one near the Magsafe is more powerful..