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jowie
Jun 17, 2011, 07:22 AM
Hi all,

I've been having trouble with my old iMac G5 (17" iSight). It wouldn't boot up properly. To make matters worse, the SuperDrive doesn't work properly any more so I can't just boot off the Mac OS install disks.

Here's the story so far:


Switched iMac on, chimed, got Apple logo. Fan went crazy and didn't get any further. Tried rebooting a few times but same result.
Zapped the PRAM (command-opt-P-R) and tried again, but still no joy.
Found some instructions on the web about booting in Open Firmware mode (command-opt-O-F). Tried this, with the reset-nvram and reset-all commands (I think!) and then rebooted. Again, nothing.
Decided to be sneaky, using another computer: Switched my PM G5 on in Target Mode, plugged it into the iMac and held down the option/alt key. Chose the PM's Target disk as bootup disk. iMac started up.
While it was up and running using my PM's drive as the startup drive, I ran TechTool Pro 4, scanning hardware as well as the iMac's own drive. All passed with flying colours.
Ran Disk Utility on iMac disk... Repair Permissions found a few issues but nothing major, and Repair Disk found no errors at all.
Rebooted the machine holding down the alt key, selected the iMac drive as the startup disk. Computer booted up successfully. Removed FireWire connection completely.
At this point, I thought I was sorted. But the following morning when I tried to boot the machine, it flashed the question mark... Couldn't find the startup disk. So I held down alt again, selected the drive and booted up. At this point I went into the Startup Disk control panel to make sure the internal drive was selected.
However... Now since I've rebooted, I get nothing, even on the Startup Disk (alt) screen. The cursor spins for ages, but no drives come up. :(


So hardware-wise, it seems okay, so I'm guessing it's repairable, don't you think? I did have one thought... The machine's getting on, do you think it might be the PRAM battery?

Thanks for any advice!

:-Joe



Nameci
Jun 17, 2011, 07:33 AM
the hdd on your imac might be dying... backup files and replace hdd...

jowie
Jun 17, 2011, 07:34 AM
the hdd on your imac might be dying... backup files and replace hdd...
That's what I thought... But I tested it in both TechTool Pro and Disk Utility, with no errors. I have everything backed up onto Time Capsule so it's not a worry. Do you still think it might be the HD?

max••
Jun 17, 2011, 07:46 AM
That's what I thought... But I tested it in both TechTool Pro and Disk Utility, with no errors. I have everything backed up onto Time Capsule so it's not a worry. Do you still think it might be the HD?

even if a drive seems ok it could still fail, i suspect the hdd too

jowie
Jun 17, 2011, 07:54 AM
even if a drive seems ok it could still fail, i suspect the hdd too
Doing any kind of repair on the iSight iMacs is pretty tough... Perhaps I should replace the PRAM battery while I'm at it anyway, to be on the safe side? The machine must be a good 6-7 years old now.

max••
Jun 17, 2011, 08:06 AM
Doing any kind of repair on the iSight iMacs is pretty tough... Perhaps I should replace the PRAM battery while I'm at it anyway, to be on the safe side? The machine must be a good 6-7 years old now.

Personally i wouldn't bother, in my experience i have had no problem running macs with dead pram batteries, in fact i think all my macs execpet my macmini g4 have dead pram batteries and run fine, but if you get board with it saying that your clock is set before XXXX ( i forget when it says) you should replace it

jowie
Jun 17, 2011, 08:21 AM
Hmmm okay thanks :) So it's looking like a new HD then... Actually at least the repair job for that won't be so bad.

I need to "trade in" the machine on eBay for an Intel iMac, so I'm currently contemplating either:


Selling the iMac on eBay as-is, hoping someone will buy it in the state it is and upgrade the HD themselves... Only problem is that its resale value might be a lot lower as a result
Replace the iMac's HD, carry on using it for a couple more months, then sell it on eBay - hopefully giving it a better resale value


What do you think I should do?

stroked
Jun 17, 2011, 09:13 AM
I have read that it is hard to work on the G5 imacs, especially if you haven't done it before. I think I would try it, because it wouldn't bring much on ebay, like it is. Another option would be to use it with an external drive.

jowie
Jun 17, 2011, 11:03 AM
Better buy a Torx set and get cracking then... :eek:

stroked
Jun 17, 2011, 11:43 AM
Better buy a Torx set and get cracking then... :eek:

Good luck. Here is a guide that might help.

http://www.ifixit.com/Guide/Repair/iMac-G5-17-Inch-Model-A1144-Hard-Drive-Replacement/948/1

jowie
Jun 18, 2011, 03:46 AM
Thanks... That's what I was planning on using. Don't think I'd dare attempt the job without it! :D

mike457
Jun 18, 2011, 01:53 PM
I have tried this myself. The step I had most trouble with was removing the foil. You need to be careful not to tear it, or it causes thermal problems on reassembly. To be honest, I wouldn't try it again, but my eyesight is not as good as it used to be! :)

stroked
Jun 18, 2011, 02:18 PM
Thanks... That's what I was planning on using. Don't think I'd dare attempt the job without it! :D

Let us know it goes. I'm curious if you have any problems using the card to separate the case. I believe your G5 is put together like my first generation intel imac, and it will not be long before I have to work on it.

jowie
Jun 18, 2011, 04:57 PM
I have tried this myself. The step I had most trouble with was removing the foil. You need to be careful not to tear it, or it causes thermal problems on reassembly. To be honest, I wouldn't try it again, but my eyesight is not as good as it used to be! :)
I've experienced "the foil" before when doing a recce on a cinema display, but thanks for the warning... I think I'll I start on the job in the morning (when I get the replacement HD) to make sure I've got a good amount of daylight and can take it slowly!

jowie
Jun 18, 2011, 05:01 PM
Let us know it goes. I'm curious if you have any problems using the card to separate the case. I believe your G5 is put together like my first generation intel imac, and it will not be long before I have to work on it.
Will do. It's quite upsetting when you look at the slightly older models without the iSight, how well designed they were internally and how easy it was to upgrade them! Ah well... *rolls up sleeves* ;)

stroked
Jun 18, 2011, 05:59 PM
Will do. It's quite upsetting when you look at the slightly older models without the iSight, how well designed they were internally and how easy it was to upgrade them! Ah well... *rolls up sleeves* ;)

This is why I'm studying to build a Hackintosh. Everything apple makes, except the mac pro, is disposable.

jowie
Jun 25, 2011, 01:39 PM
So, I bought a nice shiny new 250GB WD Caviar Blue and a set of Torx screwdrivers, opened up iFixit and got to work. Installed the new HD with no problems and reassembled the machine.

I then booted up from a Leopard installer disc (via FW Target drive), formatted the new HD all fine and installed Leopard. When it came time to restart I clicked the button, got a chime and an Apple logo, then... Nothing. :(

Waited about 20 minutes, still nothing. In fact, I'm back where I started. Looks like it wasn't the drive after all. Could there be a serious problem with the internal drive bus or the motherboard? Should I give up? I know there's a problem with the optical drive, maybe I should try disconnecting it?

It's a really weird one, because it sees the internal drive, it'll format the internal drive and it will even install a new OS on the internal drive. And I can boot up from any disk over FW. It just refuses to boot from the internal drive.

Any ideas would be gratefully received thanks. Otherwise it looks like this old iMac's gonna have to be sold for parts on eBay. :(