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G4 constant crashes...Hardware issue?

The 1st 2 crashes look like USB. The last crash.. there's absolutely nothing in the logs that indicates a problem. As you can see, there's 30+ minutes of nothing and then the computer is restarted.

Code: 
Nov 21 18:52:00 localhost xinetd[315]: Started working: 2 available services
Nov 21 18:52:01 localhost SystemStarter: Startup complete. 
Nov 21 19:28:30 localhost syslogd: restart
Nov 21 19:28:35 localhost syslogd: kernel boot file is /mach_kernel
 
Jigglelicious said:
Sounds to me like your CPU might be overheating. Thats one of the classic signs of a computer freezing up. You might also have a dying hard drive, although that might cause things to freeze up temporarily, not permanently. Try the following:

Open up your case and check the CPU heatsink. Is it covered with dust? Try cleaning it. Is the CPU fan working? It might have gotten clogged with dust and slowed down over the years.

One of the simplest ways to check if its your CPU is to run a processor intensive task and see if that causes the computer to lock up faster. Try ripping a CD into iTunes, converting a DVD into a divx, or some other CPU intensive task. Something I always use is Chess - I set the computer to go against itself, and I set the difficulty to the hardest skill level. This usually heats things up quickly. If the computer locks up right away during these intensive tasks, then you can be pretty sure that something is overheating.
Click to expand...


I have strong doubts that it's the hard drive, as I have tried 2 different hard drives with no change in the crashes. As far as processor overheating, thats certainly a possibility. Might explain why after it crashes somtetimes I have to wait a while before it will start back up. I have tried running the computer with the case open, and a big house fan blowing across it. I know, its ghetto, but it eventualy still locked up. Is ther any way to check the operating temp on this Mac like you can on a windows machine?

I don't know that processor-intensive actions increase or decrease the liklihood of a crash. It still locks up if you leave it sitting alone, I don't notice it locking up any sooner or later depending on usage.
 
yellow said:
The 1st 2 crashes look like USB. The last crash.. there's absolutely nothing in the logs that indicates a problem. As you can see, there's 30+ minutes of nothing and then the computer is restarted.

Code: 
Nov 21 18:52:00 localhost xinetd[315]: Started working: 2 available services
Nov 21 18:52:01 localhost SystemStarter: Startup complete. 
Nov 21 19:28:30 localhost syslogd: restart
Nov 21 19:28:35 localhost syslogd: kernel boot file is /mach_kernel
Click to expand...

Yes. The first crash DID happen after a usb device was plugged in. It was then removed. The 30 minutes of inactivity is an example of leaving it sit there unused, and it still locks up. That way, I didn't add a bunch of stuff into the log file while still having teh computer lock up. I just used my windows machine while I was waiting for it to freeze :p
 
BTW, I am very happy (and impressed) with the help I have/am receiving on this site. You guys rule, and will hopefully prove to be lifesavers for this Mac.
 
Which is not a good thing.. if it was something software related, you'd miost likely see a splat in the log before it went south. As it is, there's nothing there, and you're seeing a freeze. (No kernel panic, right?)

So, I put forth that it's a hardware failure of some sort. Which makes it MUCH harder to troubleshoot via a forum. My first suggestions would be to pull all but the original RAM and see if it still freezes. Then slowly start adding RAM back until you (hopefully) find the culprit.
 
A few more abnormal things I have noticed in the past year's worth of dealing with this problem. Once in a while when it locks it makes an odd noise, or sound skips, if the audio is being used while it freezes.
 
yellow said:
Which is not a good thing.. if it was something software related, you'd miost likely see a splat in the log before it went south. As it is, there's nothing there, and you're seeing a freeze. (No kernel panic, right?)

So, I put forth that it's a hardware failure of some sort. Which makes it MUCH harder to troubleshoot via a forum. My first suggestions would be to pull all but the original RAM and see if it still freezes. Then slowly start adding RAM back until you (hopefully) find the culprit.
Click to expand...

Not sure what kernel panic is, but theres no visible error. Just frozen and requires me to hold the button on the front for 5 secs. And like you mentioned, it doesnt seem to log anything when it goes down...just STOPS and then starts logging upon restart.

I don't know what the original RAM is, if I even have it. I bought the computer used and it seemed to have upgraded RAM. I'm not sure if there are two macthing (brand-wise) sticks. I have 3 or 4 sticks total, tho 2 have been removed during troubleshooting. Is there a particular brand these G4's typically shipped w/?
 
rt30000 said:
Thanks. I notivced it crashed the first time when I plugged in the USB card reader. I have ran the computer with just a mouse + keyboard, and even went as far as to steal the keyboard from the wife's iMac. It would still freeze up.

Whe you see the low power warning, that was when i plugged the card reader into the keyboard I then plugged it into the back of the computer and it froze. BUT, I usually dont have the card reader plugged in. In fact, it was removed after that freeze, so the next 3 are all without that USB device connected.
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Not a good idea to connect any device to the keyboard USB port, except the mouse. Connect it at the computer. With the keyboard and mouse connected together, you're at max with the bus power of that USB port. I would suggest using a powered hub for any other connections; i.e., printer, card reader, camera, etc. It also tells me that the card reader may be defective, or the cable may be bad.
Your RAM should be a CL2, PC100. I think you have a CL322, which may cause problems for you. If you use a PC133, you may get away with a CL3; though, in my experience, that has caused problems. Others may have had different experiences, but I can only relate to what I have encountered.

You may also want to check you CPU heat sink to make sure it's seated properly and mounted correctly to the processor, including the thermal grease between the CPU and the heat sink. Not sure of your skills when it comes to playing with hardware components, but I would advise caution in that area.:eek:
 
rt30000 said:
A few more abnormal things I have noticed in the past year's worth of dealing with this problem. Once in a while when it locks it makes an odd noise, or sound skips, if the audio is being used while it freezes.
Click to expand...
A sure sign of overheating. :eek:
 
yenko said:
Not a good idea to connect any device to the keyboard USB port, except the mouse. Connect it at the computer. With the keyboard and mouse connected together, you're at max with the bus power of that USB port. I would suggest using a powered hub for any other connections; i.e., printer, card reader, camera, etc. It also tells me that the card reader may be defective, or the cable may be bad.
Your RAM should be a CL2, PC100. I think you have a CL322, which may cause problems for you. If you use a PC133, you may get away with a CL3; though, in my experience, that has caused problems. Others may have had different experiences, but I can only relate to what I have encountered.

You may also want to check you CPU heat sink to make sure it's seated properly and mounted correctly to the processor, including the thermal grease between the CPU and the heat sink. Not sure of your skills when it comes to playing with hardware components, but I would advise caution in that area.:eek:
Click to expand...

Well, I just built a windows machine. I'm comfortable with checking it. I actually already had checked to make sure it was still seatd properly, but i did not check for the thermal grease. I have one of those silly anti-static wristbands for when Im playing inside the box. lol. I'll post the #'s from allmy RAM sticks this evening, and perhaps someone can tell me which one or two to throw back in to test.
 
yenko said:
A sure sign of overheating. :eek:
Click to expand...

So, how can I check if its overheating? What are the posible solutions if so? If I find that it IS overheating, could there be permanent damage to any of the hardware components? As I mentioned way earlier, it DOES seem to work a bit better when its cooler in my house. Sometimes in the summer (no A/C) it didnt seem to work hardly at all. I thought it may be humidity related which is why I got a big dehumidifier. But, its been 60° in my house right now and it still locks up.
 
Definition of a Kernel Panic.

Look familiar?



As for the RAM, just choose a single stick then and start swapping them in and out to try and see if you can find a bogus culprit. Yes, it's a pain in the ass, but it's free for the moment.
 
yellow said:
Definition of a Kernel Panic.

Look familiar?
Click to expand...

YES! I havent seen it in a while. I use to see it ALL the time on this same machine. Nice to know what the heck it's called now! From the link you supplied I just read this:

A kernel panic in Mac OS X 10.3 or later

Mac OS X 10.2 introduces automatic kernel panic logging, so you may not see any visual indication of a kernel panic. You can check the kernel panic log any time that you must force restart your computer, using either the power button, interrupt button, or the Control-Command-power key combination. The kernel panic text is added to the log the next time you restart the computer, assuming that you have not reset PRAM at the same time (the kernel panic text is stored in PRAM until you restart). The file is named "panic.log", and it is located on your startup disk at:

/Library/Logs/



So...I will check that log tonite (unless its the same log that the system profiler pulled and I posted earlier)
 
rt30000 said:
So, how can I check if its overheating?
Click to expand...
Put your finger on the CPU heat sink. If you can't hold it there more than a few seconds, that's running too hot.
What are the posible solutions if so?
Click to expand...
Remove the heat sink. Clean the contact area of both the CPU and the heat sink itself and apply a tiny amount of thermal grease to the CPU. Re-install the heat sink on to the CPU and fasten it with the clips.
If I find that it IS overheating, could there be permanent damage to any of the hardware components?
Click to expand...
Very possible considering the time that it's been happening.
As I mentioned way earlier, it DOES seem to work a bit better when its cooler in my house. Sometimes in the summer (no A/C) it didnt seem to work hardly at all. I thought it may be humidity related which is why I got a big dehumidifier. But, its been 60° in my house right now and it still locks up.
Click to expand...
Check to physically see that the power supply fan is actually running. If there is another fan inside the case, make sure it's also running. Don't just listen for the noise; verify it by looking.

Check the RAM by touching it too see if it's hot. It should be fairly warm, but not hot. Hot is bad RAM. Remove it.
I would first verify all the sticks to make sure they're correct before inserting them into the machine. (PC100, CL2) ;)
 
I imagine you're being overwhelmed with suggestions at the moment, but just to clarify my original diagnosis, I don't suspect that you are "overheating" because there's no reason to think that your Mac is generating any more heat than normal. But what is happening might be heat-related just the same. Repeated heat-cooling cycles inside the machine produces small subtle swell-shrink effects. Even under normal operating conditions, this can cause chips to wiggle out of their seats and weak traces on the board to become open or short. This could be happening in your case. Hard to say for certain, but the symptoms you report do suggest it.

Based on your crash logs, USB also seems to be implicated. Poor USB connections can cause crashes. I've seen it myself. The easiest way to diagnose this as a cause is to disconnect all of your USB devices (including keyboard and mouse), start up the Mac and let it run that way.

Also, if you've had to hard-reboot the Mac, you've almost certainly done damage to the HD directory, which does not heal on its own, and only complicates your problems. You should reboot in Single User Mode after each incident and repair it. Hold down the "S" key on reboot until you see the white characters on a black screen. At the prompt, type:

fsck -f [including the space, then return]

When the disk and repairs (if any) are completed, at the prompt type:

reboot [return]
 
IJ Reilly said:
I imagine you're being overwhelmed with suggestions at the moment,...
Click to expand...

A little bit, but I would much rather have more information/guidance than too little!

I am more excited at how helpful you all are. Gives me renewed hope that this problem can be figured out. I can't recall the last time I posted several questions and had some (let alone ALL) of them answered. Thx guys.

So, heres what I will try, feel free to give me additional suggestions or ideas:

(1)Start computer holding 'S' and run fsck.
(2)If still freezing, replace RAM (Probably use a single stick for now, try to find one of the types aforementioned.) Being a dual processor, is it necessary in this model to run matched RAM? If so, which slots are paired?
(3)Run computer without any USB devices. This part I have a question about: How do I know if it locks up if I can't use a mouse or keyboard? I also would have to turn off preferences for screensavers and sleep. Perhaps leave it on a moving screensaver and see if that stops/freezes?
(4)See if temperature monitor can find/use any possible temp sensors my computer *may* have. Refer to "hand-sensing" temp if not. How important is the thermo grease? Would that actually cause this?!?
(5)If still crashing, stab computer repeatedly and blame a higher power. (JOKING)
 
Oh.. you have it set to sleep? Then it's not likely to be heat related if it's falling asleep.

I'd make sure that all sleep functions are disabled for the moment and then see if it crashes.

And no, the RAM doesn't have to be paired.
 
yellow said:
Oh.. you have it set to sleep? Then it's not likely to be heat related if it's falling asleep.

I'd make sure that all sleep functions are disabled for the moment and then see if it crashes.

And no, the RAM doesn't have to be paired.
Click to expand...

It doesnt go to sleep right away. Usually it freezes up while I'm using it. I never leave it sitting unattended, I start it up while I use it, then shut it down (though RARELY does it stay running long enough to actually "finish" using it without freezing up first). It went into sleep yesterday, but I awoke it so I would know when it froze up. Maybe I SHOULD put it on a moving screensaver and be certain it still crashes while in sleep. Or is a screensaver not the same as sleeping? I know that a lot of times when I leave it for a bit and I come back it is frozen. Man...theres a lot of variables involved. At least I have lots of things to try now. I ran out of the stuff I already thought of.
 
In that case, I can't be sure it is locking up when its in "sleep". I was thinking about when it shuts the monitor down (or plays a screensaver).
 
I would disable all the 'powersaving modes' for the moment, as a troubleshooting step. Screensaver is OK to leave as is.. and one that is moving would definitely help with identifying if it's frozen or not. And then continue as normal.
 
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