PowerBook not booting. Blue screen.
 

Sigh. Things are looking bad...

I put in a scratched CD to check if it was readable. The drive went into an endless loop, trying to access, I couldn't halt the process, so I rebooted. When the display came up, it was a garbled grab of the last screen, then it cleared up, then the startup stopped.

I tried a few reboots from my external HD mirror and CD, but it either stopped at a garbled screen or a clean blue screen.

The one time I did manage to get it to boot was after resetting PRAM. I then managed to get the boot disk options PowerBook/external HD/Disk Warrior CD.

I ran DW, and it fixed a bunch of problems, and the recreated directory looked fine. Also, the process confirmed that the SuperDrive and internal HD were working fine. So, satisfied that we were okay, I rebooted. Since, I have had no success booting from any of the 3 drives.

I'm seeing a predominantly blue screen with about half an inch at the top in garbled colours, along with some random white dots all over the blue. After a while, it resolves to a flat blue, but doesn't go any further. Because the garbled stuff and random dots disappear, I suspect that it's not a hardware problem (so I'm not really sure if I'm posting in the right forum). A couple of times, I've even got the gray startup screen, but seem to end up with the blue.

I booted from DVD and let it sit for an hour or so. It finally gave me a kernel panic. I rebooted, but same situation. I've reset the PRAM, NVRAM, and PMU. No help. Tried SafeBoot, but no help.
Any guidance would be appreciated.

I have an update to this problem. Yesterday, I got the machine to boot up. I was in the process of updating my post with some new info but couldn't proceed. Anyway, the only new information I gleaned from Console was something about a 'disk alignment' error (don't remember the exact phrase). What could this be?

I did put in new RAM, but that was months ago and it has performed perfectly since. I'm not sure if my problem is indicative at all of any RAM trouble. Any insights please?

You could check the RAM with 'memtest':
http://www.memtestosx.org/

And it would be best to copy the exact messages from the logs and show us.

Thank you, Hayne. Right now, I can't do anything much apart from stare at a blue screen. Logs and memtest, like everything else, are hardly accessible at the moment. I'm away from my machine till Monday. Will remove the RAM and retry when I get back. Are the symptoms consistent with bad RAM? I would have thought that defective RAM, if any, would just not show up, rather than bluescreen me.

The symptoms of bad RAM are random problems. If the RAM is bad, anything can happen, at any time.

But since you only recently started having problems, I think it is more likely a disk problem or something else.

Note that you could boot it from an external disk that has OS X installed on it. Then you could access the log files (they would be in the folder /Volumes/name_of_your_drive/var/log)

Hayne,

Thanks for your tips. However, as I had posted initially, I'm not being able to boot from my external mirror either. I'm worried that it may be a logic board problem. Why this is particularly worrisome is that less than a year ago, I had the logic board replaced (by Preowned Electronics, a third-party shop) since I couldn't afford the Apple out-of-warranty repairs. I'll be back with my machine tomorrow and will try to swap out the RAM and see if that helps. (Or, a little hopefully at that, whether the 3-day holiday has changed things for my PowerBook!)

Removing/rebooting/reseating the RAM did not change anything. So we can resolve that the RAM is not at fault.

I've done some more trouble-shooting, and here's a summary of the problem.

During normal boot, I get this garbled screen with about half an inch of contrasting screen at the top. The disk activity seems to indicate that bootup is proceeding normally. At the end, I have a blue screen, no cursor, no finder.

Booting from an external disk (achieved by pressing option at start, then blindly navigating to my secondary disk, and pressing enter!) changes nothing.

Booting from a CD/DVD is the same.

Safeboot has the same result, except that I have a cursor. So I should presume that the system has loaded.

If I boot with a dual monitor connected, I sometimes get a clear gray display on the secondary monitor, with the apple and the wagon wheel. However, this too resolves into a blue monitor. Safeboot once gave me a perpetually spinning wheel or a blue screen with a cursor (which follows screen spanning.)

Any suggestions, wise ones? I'm just hoping that it isn't a hardware problem. Somehow, my gut says it isn't, but then it isn't a very educated gut...

Please help.
 

Further desperate troubleshooting.

Safeboot with a dual monitor gives me the default desktop pattern on the second monitor. The primary monitor ends up a flat purplish blue, with some blocky vertical lines and a thin strip of pixel garbage at the bottom. And a moveable cursor with screen-spanning capability, which I can toggle to mirror mode!

Booting from a DVD, I hear the full range of disk access noises, approximately long enough to resemble a full boot-up. I end up with blue screens on both monitors. Again, a moveable cursor with screen-spanning capability, but cannot toggle to mirror mode.

option-booting gives me a pattern of thin vertical bars, except the thin strip of pixellated gibberish on top on the primary monitor. If I proceed with the boot, I end up with the flat blue on both monitors.

Starting up in single-user mode or verbose mode gives me a clear display on the secondary monitor. However, it stops at the first screen, at the last line, 'BSM auditing present'

After I reset the PMU (just plain desperate and willing to try anything) I got the additional line, 'ApplePMU::CLOCK RESET!! PMU WAS PROBABLY RESET SOMEHOW!!' and the screen accordingly stopped one line earlier, at 'Security auditing service present'

In verbose mode, I get a longer sequence of code. The last line which I can discern is 'Resetting IOCatalogue'. Then I get my familiar flat blue screen. I've tried to invoke fsck when I see a prompt, but am not quite sure what to do.

My questions now:
1. The obvious. Does anyone have any idea what I am suffering from?
2. I am option-booting blind. I'm not sure how to switch disks without any visual cue. Should I use the right cursor key to skip to the next bootable disk or should I tab? If you can help me with this, I can reliably boot from my backup drive and see if that works for me.
3. Is there any way I can run fsck at boot? Would starting up with cmd-f depressed do the trick?

I want to thank Hayne for his responses. Could some more of you wise folk spend a bit of time on my problem? If it is irretrievably a hardware failure, I will have to simply do without a computer for anything up to a year (shudder!) Since my job as a volunteer teacher pays nothing, I can hardly ask the family to fork up for another computer. Hence the slightly desperate note, for which I hope that I am forgiven.

Save me from the dark side
 

This board has been so great that I refuse to believe that nobody has an insight into my problem. I guess this qualifies as a bump, but may I seek the mods' indulgence?

I'm typing this on a Wintel machine, which I do not enjoy.

I'm not sure if I'm completely understanding what happens when you boot to single user mode. Do you get a command prompt or not?

If you get a command prompt, then directions for running fsck are here, under "File System Check". Of course, if you're not getting a command prompt, that won't work.

Trevor

Your description of garbled text and pixellated stuff makes this sound very much like a hardware problem with the graphics card.
It might help if you could post some photos of the screens - maybe someone else (not me - I'm a software guy) would be able to diagnose a hardware problem from seeing the symptoms.

But you should also pursue the single-user mode avenue.
Certainly do 'fsck -fy'
But also have a look at the log files. These are in the folder /var/log
The most important is "system.log"
You can see the contents of system.log from single-user mode via commands like:

more /var/log/system.log
(this will show you the contents page by page, starting at the beginning of the file - press space to go down a page)

pico /var/log/system.log
(See the section on editing text files in this Unix FAQ for an intro to the 'pico' editor)

You want to look for the messages from the last time you tried to boot normally (not single-user mode boot)

Thanks, Hayne, Trevor. I can't run fsck since I'm not getting a command prompt. And I can't get to a point where I can make a screen grab. It does look like a hardware problem, but I'm puzzled why the secondary monitor is getting a clean signal. Also, why is the startup halting before I get a prompt? As I've mentioned, in single-user or verbose mode, it's all looking okay till a specific and consistent point. What exactly loads or starts at that point in a normal startup? Perhaps that would be a clue.

I was asking for photographs (with a camera) of the screens - not screen grabs.

It might be interesting to try booting from an external FireWire disk that has OS X installed on it.

I would try and locate another Mac and then try it in Target Mode -- I've had a lot of good success with that in the past even with machines that couldn't boot for one reason or another. At the very least you could back up your data and run Disk Utility.

Duh!!! See how habit makes dullards of us all. It never crossed my mind that there is a simple way of getting a picture of the screen! I will shoot the screen and post results in a day or two.

So I've got my entire disk mirrored to an external FW disk. However, I'm at a loss how to force the machine to boot from this. This (below) was one of my earlier questions

I've since tried both cursor and tab and neither has apparently forced a boot from my external FW disk.

Booted my PowerBook in Target Disk mode (thanks for the heads-up, Frission) and connected to my school eMac. Mounted fine, all files seem to be in order. Disk Utility ran Disk Verify successfully, no errors. However disk permissions (repair as well as verify) were grayed out. Does this mean there is some defect and Disk Utility is unable to see a valid OS installation?

Also, which logs would be the most valuable in diagnosing a fault? I can access these, but am not sure which to look into.

Please keep the tips coming
 

Please don't give up on me here. I still need tips on

1. How to boot from my external disk without any visual feedback.
2. Which logs to look into for info regarding my problem.
3. Why does my internal disk not show access to Permissions when booted in Target Disk mode? Is that inherent in the mode or is something wrong with my installation?

I still haven't managed screenshots of my defective display. Will post as soon as I can.

Preowned has not responded to my mails. It is over 10 months since they fixed the machine, so I don't know if they will do anything. Just hoping...

You should only run Repair Permissions on the current booted drive. Since the PowerBook is mounted in FireWire Target Disk Mode, it's not the current boot drive (if I'm understanding the way you're set up correctly), so you can't run Repair Permissions.

And, in any event, Repair Permissions is unlikely to help. While "Repair Disk" could possibly help, since you report that you have run Disk Verify successfully with no errors, that is doubtful as well.

Check /var/log/system.log for info regarding your problem.

I don't understand your question about booting from external disk without visual feedback. Perhaps if you rephrased?

Trevor

Thanks, Trevor. I don't know how to boot from the external disk. Is there a keyboard shortcut that forces a boot from the external disk (like Cmd-C does for CD/DVD) ? Option-booting normally gives me a selection of bootable disks, but since I can't see the screen display, I don't know how to select. I tried tabbing and using the cursor keys, but I don't think I managed to select the external disk.

My internal disk is called PowerBook and my bootable external mirror is called PowerBack. Would the order in which they would appear (left to right) be according to disk priority (internal, then external) or alphabetical.

Sorry, just nudging this back into the light again. I still need some help with my last query above...

Sorry, I don't know the answer to your last query.

Trevor