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Startingup problem on PowerMacG3

I have a PowerMac G3 (gray, tower,266mhz, 1997).
After 2 minutes of working it froze.
After that, not possible to restart:
hardrive spins for few seconds, but screen doesnt turn on and no "opening chime" sound.
After a long rest (approx one hour), turn mac on with success: chime, screen on, loading extensions,...and
run test (succesfully) with TechToolPro. Just after that the Mac freezes and back to square one.
I tried to:
*Remove one by one the RAM cards.
*Remove PCI card (video).
*Remove Video/sound card (?), i.e.
where the audio/video output and input sockets are.
I tried both of the ram cards on another mac and they work fine.
I booted using mac OS
9.1 (both from cd and from hard drive). but this only
works after a long period wothout using the mac
(hours). the longer the break, the longer the time i
can use the mac before it freezes. i am using a power
mac g3
266 Mhz (1997).
dem ram: J3 32Mb. J4 64Mb.
video 6Mb.
backsidecache 512K.
I use tech tool pro 2 for checking.
this morning it gave an error in the finder info test.
again, it worked very well but after that it freezed
and restarting doesn't go pass the chime.
i tried to reset pram and even removed the litium
battery for ten minutes. No success.
Any clues?
thank you very much.
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Boot onto your 9.1 CD, back up all your data, WIPE the drive with a zero all data initialization, and install a fresh 9.1 system. Then add in one by one fresh copies of your applications. Do not do dirty installs. IF the problem recurs you know you have a hardware problem and not a software issue. Check the cables on your HD, and re-seat your processor card. Take the whole system outside, open it up, put your vacuum on blow and get all the dust out of it. Replace the PRAM battery.
How likely is it that your machine is simply overheating? What is the set-up like at your computer area. Is the back of the computer against a wall or other obstruction?

Like weed said open up your computer and see what is doing in there. Make sure all the fans are working properly. Try running the computer with the case open and see what happens.



Thanks folks,
I tried all this. No success!
I tried to run the mac with the case open,
without HD, cd-rom, zip, floppy, video cards..
only the daughter board (after reseating RAM
ROM, procesor and everything "seatable".)

It still froze beforeasking for startup disk.
It might be a heating problem but the fan works
fine, and the heat dissipator is not too hot
(I believe).

Again, thank you for your comments!


Youve given it a COMPLETE wipedown and reinstal?


Well as I said I even tried to restart without
any HD at all, and it froze in the same manner.

Sounds like you may have fried your motherboard. Truck it into your local Mac shop and theyll be able to replace the relevant parts.
I would try resetting the motherboard, this procedure was very successful on pre-G3 PowerMacs and may help you also. Remove all cable connections to the Mac except the keyboard. Remove the PRAM battery. Press and hold the start key on the keyboard for 30 seconds to completely drain the contents of PRAM and then reattach the powercord and startup off of the HD or a bootable CD with extensions off. If the Mac boots and stays running for more than the usual 2 minutes without freezing, shut it down, replace the PRAM battery, connect all other cables, start it back up, and reset the date and time.

If you are still experiencing freezing, I would have to agree with weed and forkbeard that you have either a thermal problem or a damaged motherboard.
what's the status on this one?


Thanks for your advice, guys.

I took the mac to an Apple center,
and indeed the  logic board was
Some days ago I got a replacement.
Everything looks all right now,
although  for some
reason when I put the mac on sleep,
the monitor turns dark, but
the fan  /hardisk doesnt slow down
and to second later it styart beeping
and it wakes up.

Any idea about that?

I've seen the same behavior on Beige G3 Macs, and it was the 3rd party USB card and/or Apple's USB card drivers, no solution was ever found other than unplugging all USB devices or disabling the USB card drivers to fix, neither of which is very practical. Set the display only to sleep. No USB card was mentioned so I don't know if this is applicable.
Zero response and finalized.
Moondancer - EE Moderator

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