Is a 120gig hard drive enough?

[definitive]

I have a 640gig hd in my mac, and about 60gigs of space used. Would an external USB 2.0 120gig hard drive be enough for me for use with Time Machine if the only part of the 640gig hard drive that I want to back up has to do with my work files which take up roughly 10-20gigs of space? Should I go with a bigger drive instead? Is FireWire really needed? How about a dedicated power plug (the drive in question is USB powered).

 

[spinnerlys]

That drive size should suffice, but depending on what HDD size (2.5" or 3.5") you get, as 250GB 2.5" HDD is not that much more expensive and will store more backups, if needed, but in your situation 120GB might be more than enough.

And USB 2.0 will also suffice, as you don't have that much data (in GB), thus USB 2.0 is fast enough. The initial backup takes the longest, so either do it at night or when you can let the iMac run on its own. Sub-sequential backups will be taking not as long, as only the change is stored. And 2.5" USB HDDs are capable of being powered via USB, mostly via one USB port on the iMac.

 

[seven7seven]

I got a WD Passport 500GB for $55 so I'd just buy a bigger one so you don't have to upgrade later.... Unless the 120GB is really cheap - I don't think they even sell them anymore