shortstuff_mt :
That sounds about right. With faster drives like an SSD the drives can be limited by the SATA speed, but spinning disks are usually limited by the disk technology itself. It's limited by how fast the drive can physically read the data from one drive and write it to another drive. A lot of spinning drives I've seen max out somewhere around 120MB/s. Data transfers between drives has very little to do with CPU speed. If you watch the CPU usage while transferring files you will see that the usage is pretty low. The HDD cache size can help a little depending on the size of the files you're transferring.
I'm glad you got your music transferred over. If your old PC isn't functional and you've copied all your important music/documents/pictures/etc... you could format the drive and leave it in your new PC as a backup drive.
Everything on the old HDD is going to be formated here in a few hours. Im putting the old hdd back in my old pc and giving it to my dad as he doesnt have a computer. Would hate to see that pc go unused. Though its old and crappy.
Has a E5700 (boy i had to deal with that cpu for 3 years, SO BAD IMO) and i put in a hd6670