First of all, apologies if you receive this more than once but my earlier post didn't seem to work. I just upgraded my cube with a new WD Caviar hard drive (80GB, 8MB buffer). I followed all the directions in the Apple Support documents as well as the Cubeowner tip about transferring the guide rail. Now my Cube has a constant hum even though everything seems to be firmly installed. It doesn't seem to matter whether the hard drive is spinning or not. Any ideas? Thanks in advance. __________________________________ Do you Yahoo!? Yahoo! Mail - 50x more storage than other providers! http://promotions.yahoo.com/new_mail