iMac will not retain startup disk setting

Question

Level 2

223 points

iMac will not retain startup disk setting

I have an Early 2008 iMac wiht 4GB and 2 external HD (1-Time Machine & 2-iTunes/iPhoto only). Occasionally, I get the spinning pinwheel of death and have to reboot. Trouble is, when it's rebooted, I get the Folder with a Questionmark. It can't fing the boot drive. If I unplug it, let it sit for 10 min, plug it back in, it sees the drive and boots normally. After I have a desktop, if I go into settings > Startup Disk, the Mac HD is NOT highlighted. It's forgotten where to boot from! I can highlight the Mac HD and go back in to check, yep, it's highlighted. But after recovering from one of it's episodes, it's not highlighted. Maybe it's having a stroke or TIA?

Tried unplugging the USB HD to boot w/o them but get the same folder & ? so I know it's not them.

Before everyone says it's the hard drive, I've had it in several times and the entire machine passes diagnostics. Additionally, it always verifies in Disk Utility and I have never lost files or had data corruption.

I thought it might be a system battery but I'm told if you don't have to update the time after unplugging got 10 min, it's not the system battery. The time never needs ot be updated. Always correect after these incidents.

Logic Board? Hmmm... new Mac!

Anyone seen this behavior or have another suggestion?

Posted on Mar 13, 2013 4:37 PM

Reply

Answer 1

Barney-15E

Level 10

112,542 points

Mar 13, 2013 4:42 PM in response to MRYFLYGUY

Try resetting the PRAM by holding down cmd-opt-p-r on restart. Keep holding until you hear the startup tone twice while holding the keys down.

http://support.apple.com/kb/HT1379

Reply

Answer 2

MRYFLYGUY Author

Level 2

223 points

Mar 13, 2013 5:00 PM in response to MRYFLYGUY

I should have mentioned... Resetting PRAM has no affect.

Reply

Answer 3

Barney-15E

Level 10

112,542 points

Mar 13, 2013 5:02 PM in response to MRYFLYGUY

How about reinstalling the OS?

Reply

Answer 4

MRYFLYGUY Author

Level 2

223 points

Mar 13, 2013 6:06 PM in response to MRYFLYGUY

Yep. Started with a fresh install & restored from Time Machine. A painful process I hope to do only once more - when I've had enough and finally replace this bad boy.

Reply

Answer 5

MRYFLYGUY Author

Level 2

223 points

Mar 17, 2013 12:56 PM in response to MRYFLYGUY

Here's another symptom. If I shutdown normally and try to restart normally, I get the folder with a "?". If I startup using the Option key, I am presented with the internal drive (and 2 external USBs), select it and the system boots normally. So the question is.. why can't the Mac see the boot disk on startup without holding the Option key?

Reply

Answer 6

Barney-15E

Level 10

112,542 points

Mar 17, 2013 12:59 PM in response to MRYFLYGUY

There is something corrupted with the disk. Not sure what. Someone else might have some other suggestions.

Reply

Answer 7

MRYFLYGUY Author

Level 2

223 points

Mar 17, 2013 1:06 PM in response to Barney-15E

That's really what it seems like, something in the boot sector. But if that's the case, why would booting with the Option key present the drive? Dose anyone know the programming behind booting with the Option key - how it's different from a normal boot?

Reply

Answer 8

Barney-15E

Level 10

112,542 points

Mar 17, 2013 2:04 PM in response to MRYFLYGUY

It just looks for drives that can boot, not for the specific drive to boot. The settings, which should be reset with a PRAM reset, are not working correctly to identify the specific disk to boot.

Reply

Answer 9

MRYFLYGUY Author

Level 2

223 points

Mar 17, 2013 4:08 PM in response to MRYFLYGUY

The only thing I haven't done is execute a normal shutdown and then let it sit for 15 min. - without unplugging the power. Not sure what that would prove. I'm thinking more and more that the drive is bad, even though it passes diagnostics.

Reply

Answer 10

MRYFLYGUY Author

Level 2

223 points

Mar 30, 2013 8:17 PM in response to MRYFLYGUY

If I kill it and let it sit 10 min. it reboots normally. Sometimes the default startup disk remains highlighted, other times it does not.

I think I isolated the SBBOD to accessing or creating files on the Mac HD. In the most recent freeze, I was backing up quicken. I select backup to disk, a finder window opens to the default save directory, click save with the default file name and the freeze begins. This happened in Firefox after choosing a bookmark file to import and frequently just trying to access/move files in Finder.

I guess a couple hundred bucks for a new drive is the last try before a new Mac.

Reply

Answer 11

MRYFLYGUY Author

Level 2

223 points

Apr 2, 2013 10:25 AM in response to MRYFLYGUY

Okay, I brought it in for one more round of diagnostics before replacing the HD. Tech reported the block scan started chewing off blocks and would then slow WAY down, almost stop. So it was a bad HD.

So don't believe what Disk Utility tells you - S.M.A.R.T verified/okay, permissions okay, diagnostics okay, etc. If the unknown folder presents at boot - even it you can recover by powering off or letting the Mac sit for a while - it's most likely the HD.

End of story, thankfully.

Reply

Answer 12

Barney-15E

Level 10

112,542 points

Apr 2, 2013 5:56 PM in response to MRYFLYGUY

SMART isn't very smart. I could hear my drive eating itself and all the while SMART said Verified. When the drive finally all out failed, the SMART status finally said it was bad.

Reply