Help. Tiger will not boot PowerMac G4

Question

I seem to have shot myself in the foot.
I have Tiger 10.4.11running on a G4 Sawtooth upgraded to 1.8Ghz via Sonnet.
It developed problems: 1. Mouse some times shot out of control and had to be steered back to where I was, 2. Could not wake computer up from sleep and had to re-start manually.
Decided to fix problems and read several options. I implemented the deletion of certain prefs:
-- trash /Library/Preferences/SystemConfiguration/com.apple.PowerManagement.plist
-- trash /Users/[username]/Library/Preferences/com.apple.systemuiserver.plist
-- reboot while resetting PRAM/NVRAM
I followed these directions; deleted the two prefs files and zapped PRAM when the computer rebooted.
However the computer would not load its OS. I tried zapping PRAM again on another re-start but to no effect.
Computer starts up, identifies HDD, Apple logo appears but the rotation symbol does not appear indicating that the computer cannot load its OS.
I have tried starting up from a Tiger Install disc but it will not work. I get a grey screen with a black rectangle in the centre reminiscent of the grey kernal panic message block but no message.
I have a duplicate (back-up) of the Tiger OS on a bootable external drive. When I start holding down Option key to display HDD’s the computer identifies both the internal and external drives with the internal highlighted. Problem is I cannot select the external drive because the computer/keyboard will not respond to the right Arrow key!
Can anyone offer a suggestion as to the cause of the problem or to its resolution. Best I can think of is to take out the HDD from the external Drive and use it to replace the HDD in the computer. That is a bit messy and I would prefer a better alternative.
I welcome any suggestions to remedy problem.

Answer 1

Hi Tony,
Glad I could help and that your efforts were not totally in vain...
We still don't know how trashing those plist files bricked your mac.
Maybe you trashed them all at once while actually you should have trashed them one at a time, rebooting inbetween, to give OSX the chance to rebuild them to default settings? They seem very essential plist files, maybe OSX can't rebuild them if the combination of these two is missing? Again, I'm no expert, just guessing.
Anyhow: for the future:
it's always best not to trash plist files. Move them to your desktop, or another location temporarily.
Test by rebooting, recreating a default plist. If you run into troubles, you can always move back the original plist file. If all goes well, you can then trash the old plist.
But I guess you figured that out by now ;-) sometimes we got to learn the hard way hehe...
Luckily you had a cloned back-up that saved your bacon :-)
regarding Leopard:
Minimum specs are 867 MHz G4 and 512MB Ram, but a mac with this specs will run Leopard significantly slower than Tiger, thus a no go. If you're well above these specs (at least 1GB RAM), the performance drop will be less significant (around 4% slower with 1GB if I remember the benchmarks well)
If you can max out the RAM to 2GB, it should run well.
another thing: I've read that Leopard Install discs are hard to get these days - at a reasonable price. A leopard disc costs much more than a Snow Leopard disc. Reason:
Leopard discs are discontinued by Apple, and only available on sites like ebay... Many people still own PPC machines where Leopard is the limit, so they are much sought after.
Also keep in mind, as I said before, that there are system specific DVD's and universal ones, the latter being more expensive.
I hope the CCC errors don't give you too much further troubles, and that your wake-up issue turns out to be fixed too, if not, best start another thread.
Side note: Should troubles continue: If you have the budget: the Mac Mini is quite affordable. I have one, (late 2012 model) and I'm very pleased with the bang for the buck. (only disadvantage: GPU not very powerful, but not an issue for me, as I don't do much graphic work)
Cheerz, see you around some day!