iMac G3 600 memory upgrade issue

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Level 1

39 points

iMac G3 600 memory upgrade issue

I have just acquired a Snow iMac 600mhz, currently using 256mb RAM (one stick). I want to install a 512mb stick in the open slot, but the computer won't start with it installed. I have upgraded the Firmware to 4.1.9, and the RAM is known good in another computer. It was purchased from OWC, and I have confirmed that the specs of the RAM match the specs set forth by Apple. I don't know what else I can do. I have attempted rudimentary things, like trying to reset the PRAM (not successful, since when restarting after the RAM install, it only beeps/bongs and sits there). I am looking for alternative reasons/solutions for this problem.

I hope someone can help me.

Thanks!

Posted on Oct 6, 2005 3:18 PM

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Answer 1

Jeff

Level 6

12,328 points

Oct 6, 2005 10:08 PM in response to Jamie Renner

At the risk of asking the obvious, are you certain that the DIMM is fully-seated in the slot, so that the eject levers are snapped closed? What are the specs for the OWC memory? What other computer did you try it in?

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Answer 2

Jamie Renner Author

Level 1

39 points

Oct 7, 2005 5:19 AM in response to Jeff

Logical question. It was very well seated in the slot. It is PC100 CL2 168-pin 3.3v 64 bit SDRAM. I assure you it is the correct RAM. And I tried it in another iMac--a friend's 500mhz Snow iMac. It worked.

As stated above, I confirmed that the firmware is up to date. I am uncertain of what else I can do. If I install just the 512 stick, all I get at startup is that little beep--no HD spinup, nothing. If I leave the existing 256 meg stick in the "first" slot, and put the 512 in the "second" slot, I get the startup sound, and then nothing else--no HD spinup, nothing. I don't know what other recourse I have. I want to make this work, but wanting something doesn't make it happen...

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Answer 3

Jeff

Level 6

12,328 points

Oct 7, 2005 10:17 AM in response to Jamie Renner

" If I leave the existing 256 meg stick in the "first" slot, and put the 512 in the "second" slot, I get the startup sound, and then nothing else--no HD spinup, nothing."

Since you can hear the startup tone with this memory configuration, did you again try zapping the PRAM by simultaneously holding down the Command + Option + P + R keys at startup, and not releasing them until the startup tone is heard for the third or fourth time?

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Answer 4

Jamie Renner Author

Level 1

39 points

Oct 7, 2005 1:01 PM in response to Jeff

Yes. I literally held down the keys for about three minutes with absolutely no results--never made a peep. Just sat there.

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Answer 5

Jamie Renner Author

Level 1

39 points

Oct 7, 2005 1:39 PM in response to Jamie Renner

OK, so I just noticed something else: the 256mb stick that was already in the computer is PC133, CL3 RAM. I was pretty sure that only CL2/2.5 RAM was supposed to be used. Do you think that it is incompatibility between the two types of RAM? If that were the case, wouldn't the 512mb stick still work in the first slot, all by itself (ie--without the 256mb stick installed)? Because it does not work by itself, and I cannot get a reset of the PRAM with any configuration involving this 512 stick. The computer runs with just the 256 installed. Do I now need to buy a PC133 CL3 512mb stick in order to make this work?

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Answer 6

Oct 7, 2005 7:07 PM in response to Jamie Renner

Jamie -

I have 2 x PC133 CL3 RAM working happily in my 600, and they both show in Apple System Profiler as PC100 CL222.

I'm wondering about your second slot. What happens if you remove the new 512 completely, and try starting up with the old 256 in that slot?

It could just be that he 512 is fine - as suggested by its working in the other machine - but that the slot's at fault.

Is the other machine running OSX? If it's 9.2.2 or earlier then that could be the explanation - the RAM could be fine for OS9, but not up to spec for the more picky OSX.

Allan

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Answer 7

Jamie Renner Author

Level 1

39 points

Oct 7, 2005 7:59 PM in response to Allan Titmuss

Yeah, the lower slot works--started up with the second slot and 256mb stick.

The other iMac was running Panther. I wouldn't think that there would be a difference in the RAM acceptance area between Jaguar and Panther, but you never know.

I am going to try and get a refund out of OWC, even though their RAM is not technically bad. I am also going to try and get another stick of 256mb PC133 and see if that works. I can live with 512mb total.

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Answer 8

Oct 9, 2005 3:36 PM in response to Jamie Renner

Jamie -

Its RAM pickyness showed up with the very first appearance of OSX, way before Panther, so you're right about that.

I think I'd try for a replacement 512. There's no reason why that size shouldn't work in your machine, and it'd be a straight swap for OWC - much easier for them.

Besides, switching to a 256 makes it look like a change of mind on your part, which wouldn't be their responsibility.

Allan

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Answer 9

Jamie Renner Author

Level 1

39 points

Oct 10, 2005 10:46 AM in response to Allan Titmuss

Thanks for the advice. OWC is sending me a new 512mb stick.

Just out of curiousity, do you think that a reset in Open Firmware might have been helpful in this situation? It just came to mind as a method of correcting other issues, but I was not sure if it would have helped in this situation.

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Answer 10

Oct 11, 2005 5:13 PM in response to Jamie Renner

Jamie -

I haven't a clue about the Open Firmware re-set, but I expect someone else here will have some input.

Good luck with the 512MB swap - let us know what happens.

Allan

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Answer 11

Ron JACKLE

Level 7

33,451 points

Oct 12, 2005 6:08 AM in response to Jamie Renner

Jamie Renner...

Open Firmware cannot fix anything that is essentially broke.

...Ron

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