PB Hardware killing ext HD?

[Earendil]

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?

 

[Makosuke]

You didn't say if one or both drives are bus powered, which would drastically increase the chance of a hardware problem frying the bridge boards, but yes, a bad port can certainly cook drives. So can a bad cable. If anything, the cable is more likely--if it's frayed internally you could be seing power-level voltage on data wires. Did both drives fry while using the same cable?

What I'd try is cracking open one of the cases, getting a known-good firewire bridge, and seeing if the drives--alone--will mount with it. If the drives themselves are having problems (past just data corruption, which could be caused by a failing bridge)--that is, they refuse to format or whatever--then it seems somewhat less likely for it to be the computer causing the failures, though it's certainly possible.

If the drives are mechanically fine, but the cases are cooked, then I'd be looking at the computer as the most likely source of damage--again, all it takes is a short from the data lines to the power ones to effectively bake a bridge board, and if it's intermittent (a poor connection internally somewhere, maybe), then that might explain why it didn't happen immediately.