[754T]

I just purchased a 1TB drive to use when backing up BOTH my 24" iMac and MacBook. Can I also move all my iTunes files to the external drive and run them from there? Does this slow down iTunes or the iMac's processing? The reason I have for moving iTunes is that I have 180 GB of music and movies that is taking up a majority of the iMac's 320GB HDD.

[Kash]

Yep. Just copy the music over and in iTunes change the default music directory, then you can safely delete the library off of your iMac.

[lightsguydave]

I used to use an external HDD because I had piffling teeny 60GB HDD inside my MB. I bought a 250GB external HDD to relieve the burden from the internal HDD. I can't say I noticed any discernible difference listening to tunes or watching movies direct from the external HDD, the USB interface seemed to cope well

You can move your iTunes library over to there, if it's established on your mac it'll be a bit of a task but here's one way to do it:

Move/copy your iTunes music folder over to your external HDD. Once you have done that, in the iTunes preferences: In Advanced, click the "general" tab. At the top is the current path for your iTunes library. Click "change" and find your new iTunes library folder on your external HDD. Hopefully this will change the path for all your tunes and you will now have shortcutted all your songs properly. Now would be a good time to check your songs all still play xD and then you're done!!!

Dave

[saxnbass]

1 more thing. If you're going to use this for your iTunes and Time Machine, AFAIK, you have to partition the HDD.