This is a cross post from the Apple OS forum. Apologies to those that frequent both forum and find cross-posting distasteful.
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I have an iMac early 2008 intel 24in.
I moved office over the weekend and now I find that after two years' service the iMac is playing up.
It will only sporadically boot from the hard drive. and when it does boot the OS is very non-responsive. In the background I can hear the drive constantly spinning up and down.
On its own I would ordinarily swap out the hard drive and see whether that makes a difference. It _feels_ like a drive problem and it is possible that a knock whilst travelling from one office to another has hurt the drive head.
HOWEVER I want to be a bit more certain as taking an iMac to bits is non-trivial. and there is a second symptom that is also present which makes me wonder:
the iMac will equally only sporadically boot from the installation DVD.
I thought that it might be that the installation media was scratched or otherwise compromised, so I tried a freshly purchased Snow Leopard disk to the same result. It's just not booting. Sometimes stuck on the cog wheel and sometimes stuck on just a grey screen - no apple logo.
i have reset the pRom. I have tried safe booting and get the useless kernel panic message telling me that it cannot find the ACPI kext. I say useless because that does not tell me what is wrong, since the symptom appears in DVD boot and hard drive boot.
sporadically I do succeed in booting from the DVD. and when I do I have tried to repair the hard drive. this runs successfully and no errors are reported. So I try to reinstall the OS but the drive does not appear in the installable locations.
By sporadically, by the way, I mean once in every 50 or 60 attempts. There is no discernible pattern to successful boots.
As said, it sounds like the hard drive is constantly powering up and down and _some_ reads are clearly successful. I suspect a damaged SATA controller on the drive but, as said, I would very much like corroboration before I give up a day to rebuilding the machine.
thanks
Justin
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I have an iMac early 2008 intel 24in.
I moved office over the weekend and now I find that after two years' service the iMac is playing up.
It will only sporadically boot from the hard drive. and when it does boot the OS is very non-responsive. In the background I can hear the drive constantly spinning up and down.
On its own I would ordinarily swap out the hard drive and see whether that makes a difference. It _feels_ like a drive problem and it is possible that a knock whilst travelling from one office to another has hurt the drive head.
HOWEVER I want to be a bit more certain as taking an iMac to bits is non-trivial. and there is a second symptom that is also present which makes me wonder:
the iMac will equally only sporadically boot from the installation DVD.
I thought that it might be that the installation media was scratched or otherwise compromised, so I tried a freshly purchased Snow Leopard disk to the same result. It's just not booting. Sometimes stuck on the cog wheel and sometimes stuck on just a grey screen - no apple logo.
i have reset the pRom. I have tried safe booting and get the useless kernel panic message telling me that it cannot find the ACPI kext. I say useless because that does not tell me what is wrong, since the symptom appears in DVD boot and hard drive boot.
sporadically I do succeed in booting from the DVD. and when I do I have tried to repair the hard drive. this runs successfully and no errors are reported. So I try to reinstall the OS but the drive does not appear in the installable locations.
By sporadically, by the way, I mean once in every 50 or 60 attempts. There is no discernible pattern to successful boots.
As said, it sounds like the hard drive is constantly powering up and down and _some_ reads are clearly successful. I suspect a damaged SATA controller on the drive but, as said, I would very much like corroboration before I give up a day to rebuilding the machine.
thanks
Justin
