Hello and Welcome to Apple Discussions.
Have an older machine with USB 3.0 or USB 2.0 ports? You'll see some speed compromise. USB 3.0 can hack most of an external SSD's speed, with theoretical max of 625MB/s, or a chunk lower in real. Dec 18, 2018 - If you really want your data to zip between your Mac and an external hard drive, then the Seagate Innov8 8TB is a brilliant choice. It uses the relatively new USB-C connection, which is found on new Macs and MacBooks, and it allows the transfer of files at much higher speeds than the ageing USB 3.0 ports can manage.
480Mbps is a theoretical maximum. The way USB2 is designed it can only achieve speeds close to that for short periods. Apple's poor implementation of USB2.0 (on PowerPC Macs at least) makes this problem worse. If you need sustained data rates, Firewire 400 or especially Firewire 800 is a much better bet:
http://www.barefeats.com/usb2.html.
Surely as a backup drive you can accept lower data transfer rate then you could on a drive you used as a scratch disk for video etc.
Cheers!
mrtotes
Dec 14, 2007 3:19 PM