About 2 days ago, I did a full backup of my Mac before erasing the entire "Macintosh HD" so I could do a fresh install of Snow Leopard (My Mac was starting up really slow). But anyways, I'm doing a normal backup and it says it has to back up roughly 50GB of data and it has been going for about 30 minutes while only backing up 62 KB. If it helps the external hard drive (usb 2.0) is a Western Digital My Passport 250GB.