Leopard wrecked my G5 SP1.8 - Firewire and DVD trashed

Question

I installed Leopard on my SP1.8 G5. Immediately following the 10.5.1 update, the machine started to develop kernel panics every two minutes. The fans went crazy and I thought the machine was going to blow up. Now I find that both Firewire 400 and 800 ports are screwed and although my Superdrive can still reads audio CDs, it thinks any other disc I insert (CD or DVD) is blank media. My G5 is stuffed as I can no longer load software in target mode or boot from a CD or DVD. I've had to buy a new MacPro now and I'm very angry. I've been a Mac technician for about seven years and so I know most of the wrinkles but this one has me defeated. Something must be wrong with the motherboard. I eventually managed to reinstall Tiger by booting over a network volume and using a network install disc image. Has anyone else had this problem with Leopard?

Answer 1

It's probably not hardware damage.
+Mac OS X Support Essentials+, edited by Owen Linzmayer, says on p. 420 that the Metallic Apple logo at the beginning of a boot sequence means that Open Firmware has found BootX. The next step, p. 421, is that "BootX attempts to load a previously cached set of device drivers. If this cache is missing or corrupt BootX searches /System/Library/Extensions for drivers and other kernel extensions… You can recognize this stage by the metallic Apple Logo and the spinning gear that appear on the screen." If your spinning gear doesn't appear (as mine didn't) it means your DVD driver cache is corrupt, as BootX can't find anything on the DVD if it can't read the DVD.
Keep trying! I eventually got my computer to boot from an external drive, and then when I shut down from that drive it apparently repaired the DVD driver cache so that the DVD drive works again. I had to reinstall Leopard onto the internal drive, as it would no longer make proper boot caches when it shutdown. (This whole mess happened two days in a row until I figured out what was happening)