I have a 2009 iMac. Was having a look at what was available in 'the sales' and I saw a number of external HD's preformated for Macs, but using only a USB 3 interface. i.e. No firewire, no ethernet.
Well, my iMac has only USB 2, and while I know it will connect to USB 3 devices, it would be at USB 2 speeds.
AFAIK there is no way to upgrade the iMac to USB3 but is there another solution?
There were some very good deals on 2 and 3tb drives, but these would be painfully slow at USB 2 speeds. I was surprised that on devices purported to be for Macs, they don't pick up compatibility with older machines.