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V.K.
11-27-2007, 01:08 AM
It's stated repeatedly in the SuperDuper! user guide that to make an external drive back up bootable it should be a Firewire drive. I'm using an USB drive for SuperDuper back ups. I made it bootable and everything seems to work fine. I can boot from it too (it is quite slow though). Is there any danger or are there any potential problems in doing that? If not why the insistence on using a Firewire drive?

dnanian
11-27-2007, 11:04 AM
Actually, it says you need to use a FireWire drive for a Power PC Mac.

USB drives won't work as startup drives for Power PC Macs (at least under all OSes before Leopard - we've had some reports that Leopard allows Power PC Macs to boot Intel, but I haven't tested this myself).

In addition, they're significantly slower than FireWire drives, can have power issues when drawing power from the USB port (sometimes requiring "vampire plugs"), step down in speed when low-speed devices are present on the same bus, etc.

So: we definitely prefer FireWire here. But, for Intel at least, USB will work for startup.

V.K.
11-27-2007, 12:50 PM
Actually, it says you need to use a FireWire drive for a Power PC Mac.

USB drives won't work as startup drives for Power PC Macs (at least under all OSes before Leopard - we've had some reports that Leopard allows Power PC Macs to boot Intel, but I haven't tested this myself).

In addition, they're significantly slower than FireWire drives, can have power issues when drawing power from the USB port (sometimes requiring "vampire plugs"), step down in speed when low-speed devices are present on the same bus, etc.

So: we definitely prefer FireWire here. But, for Intel at least, USB will work for startup.

I have a powerbook G4 and I run Tiger. As I said in my original post I can boot form an external USB drive without any problems. You are right about it being slow but I can live with it if there are no other drawbacks.

dnanian
11-27-2007, 01:04 PM
There are some systems with USB 1 ports or drives that'll work. But not many.

V.K.
11-27-2007, 11:07 PM
As I said it's all academic and doesn't really matter but my USB drive is USB 2 not 1 (see the attached pic).

dnanian
11-28-2007, 12:05 AM
I don't know then, VK: Apple clearly documents this as not working... and it hasn't worked for me.