The main issue is this, two different hard drives have ceased to function after spending some time attached to a 867mhz Titanium Powerbook by Firewire(400). Two different cases, two different HD. The trouble shooting done so far has been to plug one of the HDs into my own computer (specs below) and see what shows. Neither OSX or DiskUtility see the external HD, however system profiler sees this: ... //5 minutes later/// okay my computer wasn't seeing the disk in DiskUtility, but now it is. However I can't mount any of the 3 partitions. Also System profiler is stalling out trying to load info on my FW devices. I have the defunct HD plugged in to my 400 port, and my own external HD plugged into the 800. However I can say that system profiler was correctly identifying the defunct HD before system profiler went wacky. I'm running disk first aid now, but I hold little hope as I think this is a HD failure, perhaps the board on the case has failed/is failing. Ideas? Suggestions? Things to trouble shoot or try? Is it possible for the Firewire port on the other Powerbook to go belly up and start frying HD cases?