Passport Essential SE 750GB- starts great, finishes poorly, it at all

System:

P67-M motherboard w/USB 3

intel i5

4GB RAM

Win 7 Ultimate 64

So, I use this drive for file transfer between builds.  I can drop files on using my other machine no problem, and when I plug the drive in to the new machine it runs great for the first file. (Drag and drop using windows explorer)  When I attempt to drag a second file i get a never ending cycle of  “calculating time, calculating speed, etc.”  From here it is all down hill.  The computer runs in a state of “crash” and can only be brought back to some semblance of use by restarting.

I have read through the various levels of this forum and attempted everything i can find as far as reformatting, drive errors and such with no luck.  Any further suggestions?

What’s your other machine?