Need to backup Hard Drive

Heres the issue, I have a very large external hard drive and a large amount of music and videos on my desktop. I have backed up the data once before and It took well over 6 hours to do so (just a simple cut and paste). My issue now is that I would like to backup this data on say a monthly basis without having to copy the same information over again and take another 6 hours, or more. What software is out there that will easily backup the data and ONLY copy the new and changed data, and skip the old files?

Use Norton Ghost. It compresses the data and stores in very fast. I can back up 10 gigs in less than 15 minutes.

acronis takes about 2 mins to do 20gb for me using an esata external drive, it compressed it from 20gb to 5gb

its is saying a an hour and 13 min to back up 300gb

Don't forget the backup will only run as fast as your slowest link. So if you've got a USB hard drive it will be slow. Switch to eSATA and it will go much faster.

As for a good backup solution, I use Coban Backup. It's free and has lots of features.