so i finally have a mac

[piranha]

after all these years of lusting after one, but not being able to justify buying one new, since all of our work was linux or windows related. but some of it is now on macs as well, and i've inherited a little G4 because, well, it has problems, and its owner sloughed it off after not being able to solve them quickly.

the problems consist of random crashes and freezes. i distinguish the two because in some cases it is able to detect that it's about to crash, and asks me to reboot, while in others it just freezes up -- total freezes, which can't be broken out of with any magic key combinations. it does the latter a lot, *sigh* -- a couple of times an hour if i actually use it consistently during that time.

being as i know nothing whatsoever about macs, this is something of an adventure. i have two guesses right off -- memory, and video card problems (which could also be memory, i guess). google helped in finding one other possibility -- extensions, the examination of which i am saving for later. i've acquired a memory tester, and it finds nothing amiss, but of course a running OSX doesn't allow for all memory to be properly examined. but i can't boot into single user mode from which i could do this, and i can't find why not. i've got a root user enabled. but when i press command-s during boot (i wish somebody would be clear about just when i have to press them, and for how long, if that matters), the system either boots up as usual, or freezes right there. i don't think "open firmware" is installed, but just in case i tried pressing command-option-o-f during startup, and it resulted in nothing either.

any ideas from knowledgeable mac users?

Comments

[ckd]

Yeah, memory seems most likely.

First, try reseating it all.

Second, try pulling out all but one module.

System Profiler should tell you what modules are in, how big they are, etc.

[novazembla.livejournal.com]

Which kind of G4, the one with the screen on a stalk or the all-in-one kind? Crackerbox is one of the latter and it was having terrible problems for a while, and it turned out to be a bad memory chip that only went wonky when the machine heated up.

Did you get the disk with the Apple hardware test suite when you got the computer?

@%<

[pir-anha.livejournal.com]

it probably once had a stalk-monitor, but i only inherited the tower. it's a 400mhz powerpc G4 with 4 DIMMs at 128M each. reseating etc has already been done.

i don't think we got any disks with it, but let me check. it runs osx 10.3 now with all the latest updates.

[novazembla.livejournal.com]

Oh, sorry, I got confused. You didn't get an iMac, which -- in my model -- has been a little notorious on the heat issue.

@%<

[vanbeast.livejournal.com]

Turn the machine off, hold cmd-s, turn it on. Keep holding it until it does something. It should be almost immediate.

OF must be installed, otherwise the system wouldn't boot. I would suspect it's a timing thing. If that still fails, I would guess there's something about the keyboard that's preventing it from being initialized until after the POST.

I have to agree that it sounds like memory. You've reinstalled the OS and all that, right?

[pir-anha.livejournal.com]

no, not reinstalled anything -- the machine came from a person for whom we develop software, and it has all the development stuff on it and nothing personal, so it didn't seem necessary. i was hoping to spare myself a reinstall, but if it turns out to be an extension problem i'll certainly do that.

i have a new keyboard now, but the same thing happened with the keyboard that the machine came with (which looked to me like the original).

oh, i thought OF was a password protection thingie so normal folk can't boot into single user mode. in any case, while holding it for what seemed like forever, i hadn't tried starting to hold it while the machine is still off; i'll try that. thanks!

[vanbeast.livejournal.com]

nah, OF is something like a PC's BIOS.

I'm not quite sure what you mean by "an extension problem". OSX doesn't use extensions in the pre-OSX sense. If it has been used for development (and has the dev tools installed, which come with Stuff), I would suggest a reinstall of the OS. Particularly if it's running 10.3 and has been since 10.3 came out. Double-particularly if it was an upgrade from 10.2. Triple if.. well, you get the idea.

In your position, I'd first do the magical "yank one stick of RAM at a time until it stops". If none of that helps, I'd reinstall the OS. If it still doesn't help and you're not under AppleCare anymore, I'd buy a mac mini :) But seriously, I would.

You may consider pulling the hard drive, putting in a fresh one, and installing onto there. Then you have an easy way to restore the data you need if it works, and it's not a pain in the ass if it doesn't.