put 8gb RAM in 2009 Macbook but "About Mac" says 4gb

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Level 1

51 points

put 8gb RAM in 2009 Macbook but "About Mac" says 4gb

Recently I bought a used late-2009 Macbook (white unibody) with an official limit on maximum RAM, stated by Apple, of 4 GB. But many users report that this model, MC207LL/A, actually can handle 8 GB. I'm running OS 10.6.8, and the MB worked fine with 2 gb. I just replaced the 2 gb (2 x 1gb) with 8gb (2 x 4gb) of Crucial RAM, bought from Amazon. It then booted up OK, and programs seem to still be running fine now, but "About this Mac" and System Profiler and Activity Monitor all report only 4gb of RAM. Is anything wrong? Should all of these be reporting 8gb?

____btw, it was easy to insert the first 4gb RAM-chip (on bottom) completely, but the second (on top) was more difficult, so if the second didn't get put in properly could this cause the MB to read only 4gb? I assume that if there was improper insertion the Macbook wouldn't work at all, but I don't know what would happen. (I've changed RAM several times before -- on G3 Powerbook, G4 Tower, iMac, MB Pro -- and it always worked OK, but doing this always worries me.)

Posted on Dec 1, 2014 6:48 PM

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Answer 1

SeaPapp

Level 7

26,492 points

Dec 2, 2014 4:05 AM in response to CraigRu

Your MacBook will support 8gb of ram. Open System Profiler and click the Ram tab to see if both modules are being reported there and that they're being recognized as 4gb modules. I'd have to guess one of three things, 1. Remove and reseat the ram. 2. You've got a bad ram module. 3. You've got a failed ram slot. Troubleshooting should be pretty easy by moving the modules from one slot to the other you can pretty much figure out what the trouble is. You can also install one if the new modules with one if your old modules to test that both slots are being recognized correctly.

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Answer 2

CraigRu Author

Level 1

51 points

Dec 2, 2014 9:21 AM in response to SeaPapp

Thanks for helping, Mike. Oops, I feel foolish that I didn't "click the Ram tab." It says:

BANK 0/DIMM0 Empty Empty Empty Empty

BANK 1/DIMM1 4 GB DDR3 1067 MHz OK

____Is "BANK 0" the bottom or top slot?

____I sure hope the problem isn't your #3, which would mean I broke the ram slot because it worked OK (with 2x1gb) before I did the changing.

____Maybe it's #4 -- I just didn't push the top-slot RAM stick in far enough?

____I need this Macbook for a big project the next few days, and it now works OK as-is, so… Will it hurt anything (RAM or slot) if I just "let it be" and do the experiments ("remove and reseat the ram" etc) this weekend?

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Answer 3

SeaPapp

Level 7

26,492 points

Dec 2, 2014 10:34 AM in response to CraigRu

Based on this https://www.ifixit.com/Answers/View/76184/Why+8GB+RAM+upgrade+failed+%28Computer +sees+only+4GB%29 I believe the top slot to be Bank 0. You'll have to decide if you want to fool with it now or later...I don't know that it could do any do any damage but then again I don't know that it won't. It would be driving me crazy and I'd have to pull it apart and check, but that's just me.

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Answer 4

CraigRu Author

Level 1

51 points

Jan 12, 2015 3:19 PM in response to SeaPapp

UPDATE: the Macbook worked fine for a few weeks with the 4gb, then Chrome began saying "Snap" occasionally, then when it opened it immediately closed. So did Mail, and other programs. Obviously something was wrong. At this point I should have again "clicked the RAM Tab" to see if one slot was still "OK" and the other still "Empty" because this might have provided valuable information. Instead I did a Shut Down, and then it wouldn't ReStart. Sigh.

____One possible clue is that during an attempted ReStart the screen stayed for awhile (minutes) with a long thin rounded rectangle -- about 2.75 inches long, a little over 1/8 inch high -- showing some kind of "progress" that stopped at around 30%. It wouldn't do anything more, so eventually I gave up on the re-start.

____I re-opened the Macbook and tried pushing the top-slot RAM chip in a little further, and it seemed to "seat" solidly. Then tried a re-start but this time the rectangle(s) appeared only briefly on the screen -- or maybe two of them appeared briefly -- and then the re-start process stopped.

____Next, I took the RAM chip out of the top slot, and during a re-start it stopped more quickly than with both chips in, before I could see any rectangle(s).

____I would try more experiments, but... removing the chips requires super-strong bionic fingers and (especially for the bottom chip) with very little of the chip to "grab onto". If special tools (or special skills) are required to do this easily, I don't have them.

____I don't know if the chips are bad, or if I messed up one or both chips or slots, or if the 5-week old used computer was messed up in another way. Do you know what is happening, and why?

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Answer 5

SeaPapp

Level 7

26,492 points

Jan 12, 2015 3:58 PM in response to CraigRu

WIthout physical access it's impossible to determine which hardware is/has failed. Your best bet at this time is probably to haul it to the nearest Apple Store or AASP for a more through diagnostic.

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