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T Reisig · Apr 3, 2006, 03:39 PM

As near as I can figure, the lightning storm we had last night fried one of my USB busses and a number of USB devices. 2 USB hubs, and a port on my KVM switch no longer work. And nothing that is plugged into the left USB port on my G4 is recognized. Also, the computer will no longer shut down from the Apple menu (when you select "Shutdown" it just restarts). This may be the final nail in the coffin of this old work horse (G4 Dual 533 Digital Audio-upgraded to a dual 1.3Ghz). I'd like to try and make it last til the Intel desktops come out. My question is this: Does this seem like a powersupply issue, or a logic board (either of which could be raplaced for cheap-I'd just rather not do both if it's not necessary)? Is there some diagnostics that could point to one or the other as the problem? I ran my hardware test CD and it failed (with "scc /1/5" error). Thought that error could be because of the processor upgrade I've got.

Thanks

Tim

Waragainstsleep · Apr 3, 2006, 04:12 PM

Did it tell you which component it failed on?
Since you still have a working USB port, I would say its the board which you would have to swap to fix it. Cheaper to buy a USB2.0 PCI card. And of course faster than 1.1. Sadly you will probably not be able to transfer the card to a new Intel PowerMac as PCI-E is not backwards compatible.

tooki · Apr 3, 2006, 04:16 PM

For $25, who cares that it can't move to a new machine? Whoever ends up with this one will probably want the USB card anyway.

tooki

OreoCookie · Apr 3, 2006, 04:22 PM

Before you invest any money, make sure all other components work. Since you've run the Apple Hardware Test already and it found an error, your computer will probably be damaged. So if you'd give us more details when the Apple Hardware Test gives you that error message, we could make more educated guesses.

Other parts of your Mac might have been damaged as well. In particular RAM is sensitive to even static electricity.

T Reisig · Apr 3, 2006, 04:37 PM

The Hardware test failed on the first test (Motherboard I think). I'm not as worried about the lack of a USB port as I am with the fact that the machine won't shut down anymore. Another note. When I forced it to shut down (held the power button) then tried to start it up, it was not booting at all. Then I pulled the AC chord (at the computer) and plugged it back in and it booted as soon as the chord was plugged in. And if that means more failures are eminent then I'd rather get a new Logic board (I saw one on Ebay for around $100).

Tim

Originally Posted by OreoCookie

Before you invest any money, make sure all other components work. Since you've run the Apple Hardware Test already and it found an error, your computer will probably be damaged. So if you'd give us more details when the Apple Hardware Test gives you that error message, we could make more educated guesses.

Other parts of your Mac might have been damaged as well. In particular RAM is sensitive to even static electricity.

Waragainstsleep · Apr 3, 2006, 04:43 PM

Reset the PMU.

OreoCookie · Apr 4, 2006, 04:29 AM

The thing is that it is hard to determine which components are affected. I would second the suggestion and remove all non-essential hardware (e. g. pci scsi cards) which you do not need and then check if the bare-bone system is running stable.

I would definitely check the RAM and the cpu which could be damaged as well. If I were you, I'd try to have a friend check the RAM in another machine which you know works fine (e. g. with memtest or the Apple Hardware Test).

I suppose there was no surge protector in between the outlet and your Mac, right?

T Reisig · Apr 4, 2006, 07:51 AM

There was surge protection (just power strips with breakers). I think the failure was caused by the number of devices on the bus. The USB bus in question had a combo (FW/USB) hub, a USB Dongle (also blew up-it gets extremely hot now when it's plugged in), a KVM Switch, another USB Hub and a second keyboard on that hub. EVERY USB device on that bus is dead. The other USB bus only had a Midi interface (which appears to be fine).

Tim

Originally Posted by OreoCookie

The thing is that it is hard to determine which components are affected. I would second the suggestion and remove all non-essential hardware (e. g. pci scsi cards) which you do not need and then check if the bare-bone system is running stable.

I would definitely check the RAM and the cpu which could be damaged as well. If I were you, I'd try to have a friend check the RAM in another machine which you know works fine (e. g. with memtest or the Apple Hardware Test).

I suppose there was no surge protector in between the outlet and your Mac, right?

OreoCookie · Apr 4, 2006, 08:15 AM

I see.
Have you tested your internals with a working computer (e. g. at a friend's place)?