i have this is issure. My MBP 2.4GHz SR with 10.5.2 wont autosleep after i replaced the internal HD with WD 320GB scorpio drive (by autosleep i mean automatically sleeping after some time of inactivity) . It sleeps just fine when i do these, apple/sleep or press option+command+eject. anyway, i figured out that the hard drive is the problem because i tried many different things and it didnt autosleep. I called AC and they couldnt get it to work. as a test i booted leopard installed on an external hard drive and the MBP autoslept. This is really confusing me. can i confirm everyone is not having this problem? (i mena those who installed the WD 320GB scropio hard drive) regards.