wizkid, please don't bump threads this quickly - it's only been a few hours! If someone knows, they'll post
If you no longer use the 1st drive to boot from, then I don't see why you can't activate it on the 2nd. I upgraded my PC with a new and I activated Vista for a 2nd time (you might need to ring MS on an 0800 number though). You can't have Vista on two drives at the same time though.