Ask Different is a question and answer site for power users of Apple hardware and software. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am setting up an old iMac G4 running Mac OS X 10.5.8 as a computer to back things up from my network. I.e. it uses SSHFS to mount network shares and back up their contents (about 120GB) to a connected external LaCie rugged hard drive (the iconic orange one).

The hard drive has USB3 and FW800, both of which are not present on the iMac. However, I have a FW800 to FW400 adapter cable, and the USB3 cable works with the iMac's USB port (which is USB2 right?).

My question is which one will be faster? Does it even matter whether I use the USB3 to USB2 versus FW800 to FW400 connection? Thanks!

share|improve this question
Your iMac G4 may not have USB 2 - mine doesn't. – CajunLuke Jul 13 '12 at 17:02
up vote 5 down vote accepted

Firewire 400 will be considerably faster than USB in this case, as FW has its own dedicated chipset, whereas USB requires CPU time and shares its bus with all other USB devices.

share|improve this answer
Understood, thanks!! – hpy Jul 13 '12 at 18:18
Anytime. Remember to occasionally (and regularly) check your backups by restoring files. There are two kinds of computer users in the world - those who have lost data, and those who will.. – da4 Jul 14 '12 at 18:45

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.