WD 2.0GB green. I was surprised that although it does spin the disks at ~5900 it is not noticeably slower than the other 5 Seagate 7200.8, 7200.10 and 7200.11 drives that are currently in my mythbox. It also uses less power than any of the other drives I have except for the SSD. I got mine for around $165 new in June at ebay. John