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iMac won't start up

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PTmon

IS-IT--Management
Mar 8, 2001
284
US
I have a weird problem. Slot-loading imac had a hard drive die. I replaced it. Installed system 9.1 with no problem after formatting it. When it rebooted the screen was dark red. I rebooted and zapped the pram. It starts up, and shuts itself down now before the screen even lights up. (about 10 seconds) I've tried zapping the pram again and it just shuts down. I really don't want to take it apart again, I'm thinking maybe the PRAM battery, any other ideas?
TIA,
PT
 
Have you tried to boot from the CD? If it won't boot from the CD, you may have a hardware problem (power supply, video, etc.)

You might need to double check the connectors on the hard drive you installed as well as hard drive jumper settings.

 
I had tried to boot from cd, with the same result. What's weird is that it did start up after installing the drive. I was able to format the drive and install 9.1. The screen was red when I rebooted, like the color guns for green and blue weren't firing. THinking it might be a problem with video drivers I zapped the pram. I'll crack it back open and double check the connections tomorrow morning. Thanks,
PT
 
Okay, opened it back up, tried the old hard drive, same problem, replaced pram battery, same problem, pressed cuda button, no help. Removed and reseated every connection I could, including ram. No luck. Still chimes on startup, drive spins up, about 5 seconds later the whole machine just shuts off. Screen never lights.
Ugh.
PT
 
If you have it apart again, make sure the RAM is still solidly plugged in.

If the old hard drive was bad, I'm not sure what putting it back in proved.

What made you think the old drive was bad? Maybe there is another problem, such as the power supply, memory, or something else.

 
The old hard drive was making nasty sounds, like the bearing was going out, and frequently the iMac would show the flashing ? After repeated reboots it would spin up enough to get the data off of it. It was only a 6gig drive, so I replaced it with a 20gig. I connected the old was because while it was in the computer would at least boot to a flashing question mark, I can't get that far with the new one. However, now isn't working either. I thought maybe I had the jumper set incorrectly on the new one. (I used master) I thought perhaps it needed to be CS or something. It is entirely possible that it is some other problem, such as power supply or ram. I don't have any other ram to try, however, and no good way to test the power supply. I'll haul it off to a repair shop I guess.
Thanks,
PT
 
TMon, did you solve this problem since January?

I had a very similar experience today with my iMac, a 350MHz slot-loading iMac. I replaced the original 6GB drive with a 20GB drive, used OSX Disk Utility to partition it into two equal parts, installed 10.2 on one partition, all with no problems.

Then I installed OS9 (from original iMac disks) on the "other" partition, intending to upgrade to 9.1. After the OS 9 install, the screen was "shades of blue" on restart, as if there were no red or green tones.

I was nonetheless able to restart in OS X and get the 9.1 updater. After the 9.1 update, the restart in OS X failed.

Thereafter, the behavior was exactly as you describe: Mac "bonggg" chord sounds, can't boot, machine turns off after 10sec, screen never lights up, CD spins briefly. Tried to zap the PRAM but that didn't work (no multiple "bongggs").

I did not update firmware for this iMac (didn't know I should; should I have?)

I'd be delighted to hear how you resolved this?
 
I had to replace the motherboard. I had updated the firmware, so I don't really know of that could be your problem or not. $300 later, it's back in action. Try resetting your firmware. Other than that, hear's hoping it's not your motherboard!
Best of luck,
PT
 
Hi all
If you had read the instructions that come with OSX, it tells you to install OS 9/9.1 first, upgrade to OS 9.2 and then install OSX.
I did it this way a few weeks ago and have had no problems with either OS.
 
Mosh99,

Do you think failing to do this could have caused the currently irreversable identical problems a similar spec. machine I have is suffering from?
Can you tell me how?
What should I do now?

Paul.
 
Hi there,
I was trained in OS X by Scotsys, the main apple retailer and Repair Company in Scotland (UK). It sounds like a problem with the video Digital/Analogue controller. You need to ensure that your Firmware is up to date BEFORE installing OS X. OS X handles the power to the A/D board differently and as observed, it can cause physical damage.
Hope this is of use.
Scotty

 
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