external hard drive

[bs0604]

I have two 1 TB "Buffalo" hard drives from Other World Computing which I use to back up my computer. One I keep unplugged and stored separately. They simply plug into the USB port of my Macbook Pro. I am considering getting a third external hard drive for further redundancy. I see on the OWC site some external drives are BUS powered like my current two drives. However, others are externally powered by plugging into the household current. This seems like more of a hassle than the simpler BUS powered drives. There must be some reason externally powered drives are made?

 

[BrianBaughn]

The USB doesn't provide enough power to run a 3.5" external HD and there could be circumstances when even a 2.5" drive won't get enough power (like when it's on an unpowered hub).

 

[sfphoto]

The 3.5 inch drives are faster hence the need for AC power. My Buffalo drive has a Firewire port, yours may as well. Your MBP can boot from a Firewire external, if you ever need to. Transfer rate might well be faster too.