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sabrejim · Mar 27, 2006, 05:02 AM

Hi guys,

Last week I noticed my 12" rev b powerbook was running quite a bit slower than usual. I couldn't figure out why. Then I noticed that Activity Monitor was only showing 512mb of ram.

That was odd since I know I bought a 512mb chip to install in the ram slot in the bottom. I checked system profiler and it showed DIMM0/Built In as empty and DIMM1/J31 as the 512 I installed years ago. If I remove the 512 then the powerbook won't boot, I just get a few beeps and the sleep light glows.

I took the powerbook apart to see if anything looked loose and nothing did. I found one chip that looked somewhat like a ram chip that I reseated, although it had 2 ports on it, so that might not have been one.

I also could't find anythingrelated to this googling or any mention of the builtin ram in any fixit guides.

Does any have suggestions or has had similar problems?

Thanks

JKT · Mar 27, 2006, 06:11 AM

It could be two things - a logic board failure (which some AlBooks did suffer, though IIRC they were 15" models), or it could be a RAM failure. Run the hardware diagnostic from your installer disc to see if it reports any issues.

Tuoder · Mar 27, 2006, 11:10 AM

You reseated a ram chip? what exactly did you do when you reseated it?

sabrejim · Mar 27, 2006, 03:54 PM

Originally Posted by Tuoder

You reseated a ram chip? what exactly did you do when you reseated it?

There was some chip in about the center of the machine. It was roughly the same size as the memory I installed myself and have the gold connectors at the bottom and was wrapped in some black covering. It was also screwed down. I have no clue what this actually was, but I unscrewed it, pulled it out and saw that there was some "port" on the bottom, that plugged into the board, so I plugged it back in. Didn't seem to help or hurt either way.

I was able to find some stuff online now that it was mentioned that 15" had a massive problem with memory dissapearing. My problem appears to be the same or similar issue although I see no way to fix it myself short of a new logic board.

bloodline · Mar 28, 2006, 02:24 AM

Originally Posted by kaze0

There was some chip in about the center of the machine. It was roughly the same size as the memory I installed myself and have the gold connectors at the bottom and was wrapped in some black covering. It was also screwed down. I have no clue what this actually was, but I unscrewed it, pulled it out and saw that there was some "port" on the bottom, that plugged into the board, so I plugged it back in. Didn't seem to help or hurt either way.

Sounds like the Modem, the ram chip are soldered to the mainboard. Check out the pbfixit guides.

chipchen · Mar 28, 2006, 12:59 PM

Yea.... you reseated the modem. The on-board chip is soldered onto the logic board. Try zapping PRAM (hold "p, r, option, and cmd" as you restart and wait til you hear three chimes to let go) and try resetting open firmware (boot holding "o, f, option, and cmd" til you get to a white screen with letters. type "reset-nvram" and hit enter. then type "reset-all" and hit enter. the PB will restart.) If that doesn't work, you have a failed logic board.

sabrejim · Mar 29, 2006, 05:13 PM

Originally Posted by chipchen

Yea.... you reseated the modem. The on-board chip is soldered onto the logic board. Try zapping PRAM (hold "p, r, option, and cmd" as you restart and wait til you hear three chimes to let go) and try resetting open firmware (boot holding "o, f, option, and cmd" til you get to a white screen with letters. type "reset-nvram" and hit enter. then type "reset-all" and hit enter. the PB will restart.) If that doesn't work, you have a failed logic board.

Tried the PRAM zap and the cd drive sounds like it spins up over and over, nothing comes up while i hope those keys down.

In the system profiler in the diagnostics section it says the power on self test failed and failure type memory