Can't get my iMac G5 to Normal Boot - Freezes at Blue Screen

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Level 1

5 points

Can't get my iMac G5 to Normal Boot - Freezes at Blue Screen

Hello Everyone. Having issues with freezes on my iMac G5 2.0GHz with ALS, w/o iSight. I've read many posts here, and have pretty much done all of the suggestions. Here are the details:

Worked great for the few months that I've had it, then I noticed that occasionally the Finder menu on top would disappear. It would return once I put the mouse to the top. Then after two weeks, upon startup, the chimes would ring, the white screen with the apple showed, spin-wheel spins, then it would change to a blue screen, then a grey-blue screen showing the cursor, then freeze instead of going to the desktop. A couple of times it would load the desktop, but wouldn't respond to mouse clicks. It was running 10.5.8 I believe at the time.

I decided to Erase and Install the software with the 10.5 disk (since I didn't have many files on it), and it did erase the OS, but froze upon install. Tried several time to no avail. Starting up with the option key verified that only the DVD disk was available. So I decided to install from the original 10.4 disk, and that installed without any problems. Ran Disk Repair, and no problems found. Ran permissions repair from HD Disk Utility, and everything was OK. Ran Apple Hardware Test, and everything passed (though it took 80 minutes to check the 2GB of RAM during this test). However, I could not boot from the HD OS. Same freezing on blue screen.

The iMac starts up fine in Safe Boot. Even installed Office with no problems. Though the Airport Card is not recognized in Safe Boot mode. So I upgrades to OS 10.4.11 that I transferred the .dmg file from a different Mac, and it upgraded with no problems. Still Airport isn't recognized. And I cannot boot in normal mode, with the same freezing before the desktop shows.

I've run a PRAM reset, did the power-up with Apple-S keys and typed "reboot", and still no regular startup. Though I do have internet with an Ethernet cable plugged in direct. I suppose the only problems I have now, with only starting up with Safe Boot, is the Airport card functioning, and I believe I read that the sound input card may not function for recording purposes (I'm a musician).

I believe the HD is OK, as it works nicely from Safe Boot. The RAM is not original, but has been in the iMac since I've had it. Is this indicative of a partially bad logic board? Thanks in Advance! Paul

iMac 2nd Gen. G5 2.0GHz EMC No. 2055, Mac OS X (10.4.11)

Posted on Jan 26, 2011 7:00 AM

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Answer 1

Jan 26, 2011 7:10 AM in response to Paul Bower

Hi Paul and welcome to the Apple Discussions.

Here is an article that may be helpful:

http://support.apple.com/kb/TS1417

Can you startup holding the option key? That should show you the bootable partitions. If so select the hard drive and restart. Dows it then startup correctly?

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Answer 2

MGW

Level 7

27,041 points

Jan 26, 2011 7:20 AM in response to Paul Bower

Paul, you seem to have been very thorough in trying things, and thanks for letting us know everything you've done; all to often people don't tell us what they've done, and then when we suggest something, they'll say, oh I tried that already.

In your case, it does sound as if the logic board and.or airport card could be failing. Do you have access to DiskWarrior or TechToolPro? Either of them can diagnose a hardware problem and fix a corrupted directory. Is the any vestige of your previous OS applications on your new setup? Being able to function in safe mode would indicate a software conflict, try booting after removing all the startup items in your account and see if that helps.

You can also try switching the RAM around, faulty memory can cause odd problems.

Let us know how you make out,

Message was edited by: MGW

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Answer 3

Jan 26, 2011 7:30 AM in response to MGW

...all too often...

Hee, hee.

Anyway, if you open the back to switch the DIMMs take a look at the capcitors...small beer cans in a cluster...see if any are bulging.

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Answer 4

Paul Bower Author

Level 1

5 points

Jan 26, 2011 8:29 AM in response to MGW

Thanks for the very quick initial responses. I have tried booting from the Option key startup. It shows the HD as a bootable drive. Though I may not have tried since going from the clean install of 10.4 to 10.4.11. Will try again. As far as in the insides, I did pull out and place the RAM back in, as I wanted to make sure they were well seated (they were). As far as the blue capacitors, I had gently wiggled each one to verify they were well connected. I don't recall any being blown, but I should check again.

Also, I do not have either DiskWarrior or TechTool Pro. I realize they can fix quite a bit of directory issues, though are quite pricey for my $280 five-year old computer. I'll try a few more things, and post if anything new arises. I am stumped though why I cannot startup with my 10.5 DVD disk. It shows up with the Option key startup, but it also freezes when it gets to the blue-grey screen with the cursor when it, just like trying to startup in normal mode. No problem ever with the 10.4 disk on startup. And yes, this is an original Apple-branded 10.5 disk.

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Answer 5

MGW

Level 7

27,041 points

Jan 26, 2011 8:51 AM in response to Paul Bower

If it's the black disc with a big X on it, there should be no reason why you can't boot from it As far as DW and TTP are concerned, the original price is steep, but they are invaluable tools. If I had to buy only one, I would get DW. This is also abut the time your CR2032 3 volt lithium button battery may be giving out, they only cost about $5, so it might be worth replacing it. I know you reseated the RAM, but have you tried first switching them around, and then, booting with only one stick?

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Answer 6

Jan 26, 2011 12:50 PM in response to Paul Bower

I have recently had this exact issue with 4 different iMacs running 10.4.11. Upon boot they get stuck at the blue screen that says starting Mac OS X. After trying pretty much everything you tried I safe booted and deleted almost all the preferences at /Library/Preferences and also deleted all of the cache files at /Library/Caches and /System/Library/Caches. Rebooted after doing this and it started up in normal mode just fine. Hope this helps.

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Answer 7

Paul Bower Author

Level 1

5 points

Jan 26, 2011 4:01 PM in response to Calvin Orsak

I have tried with the deleting most of the Library/Preferences, and deleting all of the Library/Caches & System/Library/Caches, and still stuck at the same place trying to run a normal boot startup. Worth a try, thanks.

As far as the mentioned removing all the Startup Items, there were none in Library/Startup. I found two other Startup Items, and didn't know if I should delete either of these. They are:

System/Library/StartupItems (has 16 items in it)
System/Library/PreferencePane/ StartupDisk.prefPane

Don't want to make anything worse. Will hold off on checking the inside of the Imac until a bit later, as far as trying just a single RAM stick at a time, and the capacitor check. Thanks to all again! Paul

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Answer 8

MGW

Level 7

27,041 points

Jan 26, 2011 4:17 PM in response to Paul Bower

Look in System Prefs>Accounts>your account>startup items and remove tose.

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Answer 9

Mar 11, 2011 3:42 PM in response to Paul Bower

I just solved this for a client. Her iMac G5 ALS would stop at a blue screen. Worked fine in Safe Mode.

Eventually I decided the graphics card was bad. In Safe Mode, I opened the /System/Library/Extensions/ folder and deleted everything that started with "ATI". That did the trick. The graphics card is now disable, so videos and 3D games will run off the CPU if they work at all, but at least the iMac is usable for email and web browsing.

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Answer 10

520mac

Level 1

0 points

Aug 9, 2012 8:49 AM in response to Greg Seay

Greg Seay wrote:

In Safe Mode, I opened the /System/Library/Extensions/ folder and deleted everything that started with "ATI". That did the trick.

this.

Thanks

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Answer 11

520mac

Level 1

0 points

Aug 9, 2012 9:36 AM in response to 520mac

I should also mention that this problem first presented itself as constant pinwheeling. I couldn't exit from the screensaver. Powered down, startup would crash into Blue Screen. Safe mode boot worked, as did booting from cd. Repair disk found no errors.

So, a failed video card can first present itself as constant pinwheeling for days.

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Answer 12

Apr 30, 2013 2:39 PM in response to Greg Seay

Genius! Worked for me

Greg Seay wrote:

I just solved this for a client. Her iMac G5 ALS would stop at a blue screen. Worked fine in Safe Mode.

Eventually I decided the graphics card was bad. In Safe Mode, I opened the /System/Library/Extensions/ folder and deleted everything that started with "ATI". That did the trick. The graphics card is now disable, so videos and 3D games will run off the CPU if they work at all, but at least the iMac is usable for email and web browsing.

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