Intermittent behaviour - understanding POST codes

My MBP has an intermittent behaviour and does not turn on most of the time. But when it does, another problem occurs - there is no image on the screen (already read about NVIDIA chip issue). I have taken the MBP to two authorized shops. The first one said they were able to reproduce the NVIDIA problem, but they did not have the diagnostics software to generate an authorization code for repairing under the recall. The second one said that the logic board is bad and needs replacement, even after I told them that the MBP sometimes turns on. To me they didn´t analyse the computer enough to get past the first problem.

Doing some diagnostics at home, without any memory the computer turns on and starts beeping periodically. When I stick one memory module back, the computer sometimes doesn´t start, and the front light blinks once. If I keep pressing the power button, the front light becomes bright, fades a little, blinks rapidly for about 1 second and then turns off.

If the computer boots successfully, I hear the startup chime and hear the hard drive working, but no video.

Intel-based PC´s have some POST (Power On Self Test) codes that indicate any hw problems during startup.

I would like to know if Apple notebooks have this as well (ex: blinking front light) and what they mean.

Regarding the intermittent behaviour and the NVIDIA issue, is it feasible to:

1. Open the MBP and reseat the connectors?

2. Apply the Do-It-Yourself reflow technique (turn computer on and wrap in quilt for 1-2hrs)?

thank you,

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If you take all the memory out it is going to beep, it is suppose to. Try hooking an external monitor up to see if you get video on it. Please don't do the blanket thing.


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The Nvidia issue usually shows up as scrambled colors. You may have a RAM problem or a RAM slot problem. Try starting with just one stick and move it to the second slot starting in between changes. See if you can identify the bad stick or slot or both.

Here's the POST codes:

1 beep = no RAM installed

2 beeps = incompatible RAM types

3 beeps = no good banks

4 beeps = no good boot images in the boot ROM (and/or bad sys config block)

5 beeps = processor is not usable

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Hi Everyone.

Thank you for all your help. I took the MBP to a friend who has experience with Large Scale reflow soldering. Since the MBP was "pronounced dead" by Apple, I had nothing to lose so we opened the MBP, took the main logic board out and he reseated the Nvidia Graphics IC. Assembled the MBP back and it's working again. Don't know how long it will last, but the machine is usable again. Now just my battery that's really swollen, but that's another story (and another question). Thanks.

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Henry will be eternally grateful.
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