Hi, Don't know if anyone can throw any light on this issue, but got my new (refurb) 15.4" 3.06ghz MBP a week or so ago. It came with Seagate 320GB 7200 rpm 'ASG' drive, which I immediately upgraded to Seagate 500GB 7200rpm 'AS' drive. Anyway, the drive spins all the time regardless and won't spin down unless you close the lid. I have the energy saver set to enable drive spin down to save power, but it won't do it. Any ideas? Thank you, Mike.