iMac 5.1 SnowLeopard freezing on restart

I recently updated OS to Snow Leopard and successfully updated software. Now one week later, Software update downloads 5 updates and prompts me to restart computer. On restart the computer does initial shutdown then immediately freezes showing the "Starry field" screen.

I have disconnected an external HD, Have started the computer with the Snow Leopard DVD and successfully run Disk repair. (twice).

I have run the disc repair twice, (successfully) I have run the software update and restart 4 or 5 times always with the same freeze resulting. I have to push the power button after up to 10 minutes on the frozen screen to get any response out of the computer.

I have restarted the computer successfully from normal running (Clicked on restart in the "Apple" menu). (I did not try software update on the successful restart).

Thanks for your knowledge, help, and patients to a guy who knows little about the mysteries of his computer.

According to Mactracker, this is an older iMac (2006 model). It sounds like the hard drive is failing especially since you've stated that you have repaired the disk several times. My advice is to backup your data as soon as possible and replace the hard drive. Instructions on how to replace it can be found at www.ifixit.com. You can buy a replacement hard drive most anywhere either from a store or on line. Your iMac uses a 3.5" SATA hard drive.

Thanks for your response chscag. I appreciate your input.

I have seen the video on hard drive replacement. Looks like an adventure.

This restart freeze is the only thing I have noticed not working correctly in the computer. (It is a late 2006 model).

John can you boot from the OS X.6 DVD? Leave Installer, Go to Utilities > Disk Utility > Repair Disk and see what is reported. Not too many entries in red I hope

harryb2448 said:

John can you boot from the OS X.6 DVD? Leave Installer, Go to Utilities > Disk Utility > Repair Disk and see what is reported. Not too many entries in red I hope

Click to expand...

Thanks for your input Harry.

I did check verify disk last night and had 3 or 4 red entries. That surprised me as I had run the repair disk service and had gotten the message that the disk had been successfully repaired.

This morning I again went through the steps you advise and got the message that the disk is in need of repair. I ran disk repair and got the message that the repair is succsessful. I do still have two red entries, ( and these two red entries have been pressent after all three of my "repair disk" runs). The red entries are for;

Invalid volume file count

(It should be 520069 instead of 520072)

And the second,

Invalid volume directory count

(It should be 138640 instead of 138637)

The numbers have changed each time I run disk repair but the red entries are for the same items every time I verify the disk.

At the end of every repair, at the bottom of the message box, I get the sentence that states, "Updating boot support partitions for the volume as required" but, I don't get any indicator that the machine is done running this update. I have just left the computer alone for a period of time to see if any indicator appears, (Without seeing any such indicator), and after 5 to 10 minutes I quit disk utility and uninstall the DVD and go back to using the computer.

I am contemplating getting an SSD from Crucial and changing the hard drive out but am wondering if I am throwing good money after bad, (I just recently upgraded memory to 4GB, again from Crucial and udated OS to Snow Leopard). I have read that Apple has stopped updating security for this machine and so bought an iPad air2 to do secure actions on. Could be that the time has come to replace the desktop.

I just restarted the iMac and, before opening any apps, tried downloading the software updates again. I got the "star burst screen freeze once again. Had to hold the power button to get a response from the computer.

The computer is about 50% slower to start than normal.
Edit; After shutting down a starting up several times I believe that the computer as fast as it has ever been.

Thanks again for your thoughts, Harry.

John

Those symptoms still point to a failing hard drive.

If you don't replace that hard drive soon, you're going to be faced with a dead iMac. At least start making backups if you insist on using the machine as is.

Do as suggested John it is getting very near the total failure level. Pretty difficult job, John, but here are instructions from fixit:-


https://www.ifixit.com/Guide/iMac+Intel+17-Inch+Hard+Drive+Replacement/891


If you have to pay for the job, be careful. The iMac is getting to the stage where its value will be much less than a new drive plus labour.

O.K. guys; You've got my attention. I will make a decision on which way to go and do so soon.

Thanks very much for all of your input. Hope I can reciprocate some time in the future.

John W F said:

O.K. guys; You've got my attention. I will make a decision on which way to go and do so soon.

Thanks very much for all of your input. Hope I can reciprocate some time in the future.

Click to expand...

As mentioned, the drive is failing, and now that your attention has been piqued, download a copy of CCC (Carbon Copy Cloner) and make sure you create a full backup clone while you still can. Or maybe I missed that if a backup was already mentioned. And you can use CCC free for 30 days or 30 uses or such, unless the old SL compatible version 3.x?? is floating around somewhere.

Thanks for your input pm-r. and all others. I truly appreciate all you folks input.

I have shut the iMac down and am working with the iPad now. I need to learn what all I have to do to preserve my files no matter which direction I go from here.

I have time machine running and current. (Backing up to a WD 2 TB hard drive). I am concerned about the hard drives life expectancy as I have had poor luck with mechanical hard drives.

I really don't know how to back up the files that I am worried about losing, iPhoto, iTunes, and a folder of song lyrics and guitar chords that I have compiled over the last 15 years, (Back to the old "Egg shaped" Apple).

Do I drag and drop apps like "mail" and "iPhoto", and mymusic lyrics folder to a hard drive and reinstall them after a hard drive replacement or onto a new computer?

Thanks once again for continued input.

John

If you have Time Machine up and running you should have a current backup and be good to go. at this point you have a couple of options for restoration of your files.

1. When the new drive arrives install and format it by Boot from the Snow Leopard
a. Boot from Snow Leopard DVD and format the new hard drive.
b. Restore your files from the Time Machine backup
OR
2. Use software like Carbon Copy Cloner or Super Duper to create a bootable clone of youth drive then:
a. Install the new drive.
b. Boot from the bootable clone by holding down the Option key on startup.
c. Restore everything from the "clone" to the new drive and reboot from the new drive.

Hmmm…??? As a 25+ year Mac user and tech for almost as long, I sure hope John W F can understand and follow those directions 'cause I was having problems with the info provided, but I'm sorry but I can't improve on them right now, but maybe it's all clear to John W F.

A Time Machine is good, a backup clone is sometimes better, and a Finder copy of the Users folder, and any other critical user data, is sure better than nothing.

pm-r said:

Hmmm…??? As a 25+ year Mac user and tech for almost as long, I sure hope John W F can understand and follow those directions 'cause I was having problems with the info provided, but I'm sorry but I can't improve on them right now, but maybe it's all clear to John W F.

A Time Machine is good, a backup clone is sometimes better, and a Finder copy of the Users folder, and any other critical user data, is sure better than nothing.

Click to expand...

I'll confess that some of it flew over my head, but I did catch some of it.

I am not overly sharp on computer lingo nor navigation.

If I were to get a new desktop, and my current iMac has not stopped working altogether before I get the new desktop, could I connect the two and transfer files from old to new?

Yes. Be aware older PowerPC applications, such as Office 2004 etc., will not run on OS X.7 Lion and later, OS X.8, X.9 and X.10.

Thanks again Harry. To make sure that I understand; Are you saying that I will be able to connect the two machines and transfer files although some may not run on the newer OS?

John W F said:

I'll confess that some of it flew over my head, but I did catch some of it.

I am not overly sharp on computer lingo nor navigation.

If I were to get a new desktop, and my current iMac has not stopped working altogether before I get the new desktop, could I connect the two and transfer files from old to new?

Click to expand...

Yes, you could then use Migration Assistant, BUT… you'll probably also need a TB-FW adapter plus a proper FW 400 &/or 800 cable as the new iMacs don't have FW ports, and if you got a portable Mac, their ports are even further reduced and just don't exist.

You don't even have to do that. He says he's making Time Machine backups; just attach the Time Machine external drive to the new iMac. The first time he turns on the new iMac, the automatic Migration Assistant will run. Very easy to migrate that way. I've done it that way each time I got a new Mac. Just make sure you don't create an account on the new machine before migrating.

chscag said:

You don't even have to do that. He says he's making Time Machine backups; just attach the Time Machine external drive to the new iMac. The first time he turns on the new iMac, the automatic Migration Assistant will run. Very easy to migrate that way. I've done it that way each time I got a new Mac. Just make sure you don't create an account on the new machine before migrating.

Click to expand...

Thanks for that chscag. Sounds pretty straight forward and fairly easy.

I did manage to download the CCC program and copied my Mac HD to it. Checked the backup and it all seems to be there.

I did this to keep my options open as I may try the Hard drive replacement.

I was praying to the Mac gods during the hour and 15 minutes it took the backup to run, then the iMac froze on shutdown.

Thanks to all of you folks for your thoughts and assistance. I will post up when I am done with this project.

It took a while to gather parts and tools needed to replace the hard drive and then it took 2 fairly stressfull hours to complete the replacement.

So at this point I am screwing up my courage before plugging the machine back in and mashing the power button.

As mentioned above, I have regular time machine back up, (Including a time machine back up done immediately before unplugging the computer and opening it up for surgery).

I also cloned the computer using the CCC app, to an external hard drive.

I am wondering just what I will see when I power the computer back up. Will it act like a "New computer" and will I be able to use the "migration assistant" Chscag mentioned?

Would I be better off to start fresh from the Snow Leopard DVD and then add things, (Drag and drop?), from the clone that I made with the CCC app?

Thanks very much for continued advice.

John