Some quick advice would be helpful on this. I just ordered a new 300gb Seagate external hard drive, with both Firewire 400 and USB 2.0 ports. However, when I plug in via Firewire, no drive mounts. No drive shows in Disk Utility. When I plug in via USB the drive mounts normally and shows in Disk Utility. My feeling is that the Firewire ports on the drive are not working properly and that I will have to ship the HD back to the supplier, in this case Amazon. I just thought I'd post here and see if I'm overlooking anything, since I've never used a Firewire drive before.