So I just bought and installed the new Seagate Momentus 500GB 7200RPM 3.0Gbps drive, replacing my old Seagate 320GB 7200RPM 3.0Gbps drive. Everything went fine, but I started noticing some slowness when accessing files and moving files. Checked the system profiler and saw that my new drive was being recognized as being 1.5Gbps. I double checked to see if there was a jumper on the drive, and there's not. Otherwise I don't know what else to do. My previous drive ran at 3.0Gbps no problem. I'm thinking its a problem with the hard drive, but I just wanted a second opinion before I go through the trouble of trying a new drive.