OS X boot hangs at blue screen

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OS X boot hangs at blue screen

I returned to my computer earlier today and woke it from a sleep, and had the following issues:

1. Mouse would move but was jerky and did not affect anything (e.g. click/hover over dock icons did nothing).
2. Keyboard wouldn't respond - tried alt-tabbing to apps, force quit, force shutdown.
3. Mouse cursor had some strange faint white lines to the right of it in a box about 100x100 pixels.
4. Power button wouldn't make the Mac Pro go back to sleep.

So I had to force it to power down using the power button.

When I restarted it hung at the blue screen (sometimes the blue screen changes shade of blue a couple of times, but nothing else after that - longest I left it was 20 minutes - with no HD activity after about 3 or 4).

Note: Booting into Safe Mode everything seems to work, although the mouse movement was very sluggish on the second display (not the primary one) and the cursor still had the strange faint white lines alongside it.

Also note that my original graphics card (had the machine less than 9 months) died just last week and I am now running on a replacement sent by Apple - which I haven't had any real issues with since installing it.

Things I have tried to resolve this issue (with a reboot after each one, and where I needed to be in the OS to perform the action I did that from safe boot mode):

- Removed all login items (as I read that could cause a blue screen hang)
- Tried verbose boot, nothing seemed wrong, continued to the blue screen and hung.
- Tried booting from OS X 10.5.1 install DVD (to attempt disk repair/restore of time machine backup) but that didn't boot properly, after the apple logo, got the blue screen then the display went off completely - monitor went into the mode it is when the computer off (LED flashing, no picture).
- Tried removing second monitor
- Tried permissions repair on main system drive
- Tried re-installing the latest OS X updates by downloading the OSX Combo update 10.5.6
- Disabled auto login
- Removed an app I installed earlier today (Spotify) using AppZapper to remove it
- Reset PRAM
- Tried "force OS X start" by pressing x at startup (don't know what this does anyway).
- Disconnected everything, except monitor & power
- Verified the main boot disk - didn't show any problems
- Disconnected power, waited 30 seconds, held power button down for 10 seconds, don't know what this does but it's something that the support guy told me to do last week when I had issues with my graphics card.
- Opened it up and re-seated the graphics card (getting desperate at this point).

If I could just boot from the OS X disk I could try to repair the disk. But as you can see from above I've tried everything I can think of (and most things I've read of with regards to a blue screen hang).

Any ideas are greatly appreciated.

Mac Pro, Mac OS X (10.5.6)

Posted on Jan 4, 2009 11:11 AM

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Answer 1

The hatter

Level 9

60,980 points

Jan 4, 2009 11:37 AM in response to DEfusion

Install OS X on a new drive for testing and repairs and update that to 10.5.6 but otherwise don't install anything.

Invest in Alsoft Disk Warrior for disk maintenance and repair.

check and rule out USB / FW cables and devices (disconnect until fixed and found) and you should even suspect your mouse and keyboard if wired.

Reset the SMC by leaving it unplugged and all cables disconnected overnight and do a zap pram/nvram on first cold boot.

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Answer 2

DEfusion Author

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Jan 5, 2009 9:57 AM in response to The hatter

I tried repairing the disk via Targeted Disk Mode, it found a minor issue (with the location headers I think) and said it was repaired.

I've now managed to boot from the Leopard install disk (by holding down shift while booting with it in the drive, was trying to get into OS X safe mode, seems it made the DVD boot in safe mode too).

Tried the following:
- Restore from time machine (no go)
- Archive and Install (no go)

I also tried DiskWarrior (it too would only boot with shift held down), that fixed a few things. Said it couldn't fix a problem with environment.plist and I did notice that it wouldn't give me the option to fix permissions (said something about not having a valid OS X install).

I'm gonna try a fresh install now as that seems like my final option.

Your solution of installing OS X on a new drive and doing nothing else doesn't really seem like a solution to get my system back up and running, if I can't install anything else what's the point?

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Answer 3

The hatter

Level 9

60,980 points

Jan 5, 2009 10:01 AM in response to DEfusion

The idea of an new emergency only boot drive IS so you can boot and repair your main drive and not to use it for anything else, not for backup, not to install other programs other than tools to repair your system.

You boot from DVDs etc using "c" or using the OPTION key.

Single User Mode is sometimes an option though SHIFT key just tells the system to do a quick check of the journal and directory, and does nothing and can't work with read-only media.

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Answer 4

DEfusion Author

Level 1

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Jan 5, 2009 10:07 AM in response to The hatter

Ah I see what you mean about the emergency boot drive. But as I can do repair via targeted disk mode is there anything that an emergency boot drive would give me that I currently can't do? I suppose it would tell me whether the problem is with the drive itself or something else... it does seem very odd that I can get into safe mode, yet I can't get into OS X normally even after a restore from time machine or a archive and install.

Yeah I've tried single user mode and all sorts to fix this problem, see my original post - the applecare support person didn't offer any other advice and said he would just post me some new Leopard disks (this was before I figured out how to get it to boot by pressing shift). Seriously if I try booting from the leopard DVD (either using "c" or selecting from the menu screen presented by holding down option) then it always just ends up at a black screen with the monitor in power saving mode. The only way to get the DVD to boot is by going into the menu by holding option, selecting the CD and then holding shift as it boots.

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