Disappearing Ram and Sleep Issues Macbook pro Lion sometimes recognize 4Gb not 8Gb

Discussion in 'MacBook Pro' started by xRaRFx, Apr 18, 2012.

  1. xRaRFx macrumors newbie

    Dec 17, 2010
    Veracruz, Mexico
    I have been having an issue with the RAM on my macbook pro unibody, mid 2009 (model 5,5), since i upgraded from the original 2x1GB to 2x4GB acquired on the internet, from a certified supplier (OWC): Sometimes, the computer does not recognize one of the chips, showing only 4 Gb mounted, other times it shows both chips, thus 8 GB… but it seems to do so randomly. The ram disappears especially after a permission repair and a reboot, or a hard reboot.

    This issue occurred one week after I received the Ram, and I have checked by switching the chips with the original ones, and it occurs with the latter too, so I have excluded the possibility of defective ram. I have tested the banks, and the one in which the ram is not detected is always the lower one, never the top one (Bank 1, never bank 0).

    Since the occurring of this issue, I have also had issues with the Sleep mode: sometimes, when I send my mac to sleep by shutting the lid, it will go to sleep, only to never wake up when I open the lid, forcing me to hard reset it. the status led, when I send it to sleep, starts pulsing normally, but when I open the lid it turns off, but the display doesn't turn on, and if I close the lid the status led stays on, and after some while the fans start running (occasionally).
    this happens often, but sometimes it doesn't. here too, it seems to be on a random basis.

    If I, however, send the mac to sleep through the apple menu and then close the lid and wake it with the power button, no issue occurs.

    I have tried resetting SMC, PRAM, cleaning caches, Advanced Hardware Test from the DVD, but nothing.

    for what concerns the RAM, I have tried with both the original and the compatible ram by inserting either only in slot 0 (the uppermost slot), in which case it always is detected, and only in slot 1 (the lowermost), in which case it is never detected and the computer emits the system beep (but I believe this could be normal - I am no technician).

    Then, last week, the computer booted up showing 7.75 GB total ram, but only in one slot, and the strange thing was that it didn't recognize 8 Gb or 4, but 7.75.
    this got me worrying, a bit.

    Has anyone had the same issues? or, better, resolved the matter?

    By the way, I am running OS 10.7.3
  2. xRaRFx thread starter macrumors newbie

    Dec 17, 2010
    Veracruz, Mexico
    I don't know if this has any relation nor if it could help, but I have found that whenever I remove the RAM physically and put it back again the computer always finds the 8Gb of RAM, tho I can't keep doing it again everytime I want to edit videos cuz I do it in a regular basis.
  3. paul117 macrumors regular

    Feb 17, 2012
    might i sugest trying the orignal ram if possable?
  4. Interstella5555 macrumors 603


    Jun 30, 2008
  5. heisenberg123 macrumors 603


    Oct 31, 2010
    Hamilton, Ontario

    run this to test

  6. xRaRFx thread starter macrumors newbie

    Dec 17, 2010
    Veracruz, Mexico
    I will run some tests

    I dubt that it's a RAM issue because I have changed the position of the RAM repeatedly and the slot that sometimes disappears is always the Bank 1 (it doest matter which RAM piece is in it), but I'll test the original Apple RAM to see if it shows something.
    Thanks for the reply :)
  7. jaqueh macrumors member

    Apr 17, 2012
    dude same thing happens to me, OWC is sending me new ram sticks
  8. xRaRFx thread starter macrumors newbie

    Dec 17, 2010
    Veracruz, Mexico

    okay, I'll will call them to see what happens =)
  9. heisenberg123 macrumors 603


    Oct 31, 2010
    Hamilton, Ontario
    did you run MemTest?
  10. magicq99, Jul 16, 2012
    Last edited: Jul 16, 2012

    magicq99 macrumors newbie

    Jul 16, 2012
    Hello, I seem to experience the same issues. My Mac is a Mid 2009 17-inch MacBook Pro (running the current version of Lion).

    I upgraded the standard 2x2GB RAM with 2x4GB RAM purchased from crucial.com about 2 years ago. Everything was running fine.

    The system run perfectly well until about 2 months ago. Then I experienced the same issues as described by the user "xRaRFx".

    The system won't wake from sleep. A hard reset brings the system back up, but the system profiler reports only half of the memory.

    Shutting the computer down again and rebooting sometimes fixes the problem, but not always immediately. So far it seems to fix itself after a while by another reboot.

    When it happened again, I tried to swap the RAM slots. It was running fine again after that, but after about two weeks the problem returned again.

    A few weeks ago, when the problem reappeared, I inserted the original RAM by Apple. The system was running fine after that, so I assumed there was some sort of fault with the third-party RAM.

    However, yesterday the problem reappeared again, this time with the original RAM! So I'm inclined to rule out the memory itself.

    Removing and reinserting the RAM did not resolve the problem yesterday. An additional reboot did not solve it either.

    However, when booting the system today it's running again with the full 4GB of the Original RAM! Apparently, letting it rest for some hours while shut down fixed it again.

    Somehow the issue seems to fix itself by rebooting and/or letting the system rest for some time.

    Running the memtest program mentioned above results in "All tests passed!"

    I would also like to mention that I do NOT experience any issues while the system is running. Defective RAM or a defective slot should manifest itself in some weird crashes or system lockups, shouldn't it? But there is nothing, the systems runs perfectly well all day.

    So far the RAM slot does not "disappear" during normal operation. It only happens sometimes after waking from sleep.

    Has anyone figured out how to fix this? I have warranty on my system until December, so if the issue reappears I will contact Apple Care. However, I fear they won't be able to replicate the issue, since it only seems to happen randomly every few weeks and magically fix itself after some reboots.

    But it always starts with the system not waking from sleep. (To be exact, parts of it seem to wake from sleep, the fans are starting, but nothing else. just a black screen. only a hard reset has any effect) But again, after the issues "fixes itself", the system will run fine for several days or weeks without any issue until it suddenly reappears.
  11. acarr468 macrumors newbie

    Sep 2, 2012
    I keep having the same issue, my Mac will randomly refuse to wake from sleep and will often drop one of my 2 4Gb sticks on reboot. The Apple genius couldn't really figure it out, she recommended replacing the logic board ($310) which isn't really an option. If anyone has any other ideas what the problem might be, I would be very appreciative.

  12. Kogenesis macrumors newbie

    Jan 13, 2013
    Also having this issue

    I've got a 13-inch Mid 2009 2.26 Ghz Core 2 Duo Macbook Pro with 2x4Gb of 3rd party ram that I threw in when I first bought the computer in 2009. The waking issues began for me in December 2012 and are exactly as the other people have described. I don't know what else to do to try and solve the problem. Any suggestions?
  13. acarr468 macrumors newbie

    Sep 2, 2012
    I ended up "solving" the problem by removing a stick of RAM from the problem RAM slot. It appears that one of my RAM slots failed, so if you pull out the stick that is in the failed slot you will be fine. To see which stick is bad, go to System Information -> Memory and see which stick isn't recognized. If both are recognized, keep checking every time you wake the computer from sleep until that slot fails to load. You shouldn't have any crashing if nothing is plugged into that slot.

    The problem could be ultimately fixed with a $300 logic board replacement, but I'd rather not spend that on a 3.5 year old laptop...

    Hope this helps,
  14. quadturbo macrumors newbie

    May 11, 2010
    After trying every possible solution to this disappearing ram issue, including doing a low level format and reinstalling everything (did not work), the only thing that worked was COOLING the macbook down. In summary, I have a stock 8 gb macbook pro 2010 model with 512 ssd. I have recently noticed that I would have 4 gb of ram. THE ONLY way to get 8 gb back was to turn off the laptop for a while OR put it in the freezer for 10 minutes (yes it works consistently). After "freezing" i get all 8 gb backs.
  15. robguthrie macrumors newbie

    Feb 14, 2013
    I am getting the same problem

    I am having the same problems.

    Macbook Pro 13inch 2010 (7,1) model

    I have two sets of ram sticks, (2x2GB and 2x4GB) and the computer will not wake from sleep and occasionally reports only half the memory is present.

    Otherwise the machine is fine. Never crashes while running. I've not run memtest but I will shortly. (However I don't believe we are all just members of the "2 sets of faulty ram causing our computers to all fail the same way" club)

    I assume that the motherboard contains a fault, but, I've only been having these problems since I upgraded to 10.8 - however I'm willing to believe that that correlation is just coincidental.

    Anyone else had any luck resolving this?
  16. quadturbo macrumors newbie

    May 11, 2010
    I believe I have found a DEFINITIVE solution to an identifiable problem. I have a Macbook Pro 13" 2010, with 8 gb ram. In the last 6 months, I have had Bank 1 (4 gb) disappearing on me intermittently. In the last two months, I had consistent loss of 4 gb of ram, especially after restart. When I start cold (after 24 hours), it recognizes 8 gb, but if I restart, it recognizes only 4 gb. I would stick the macbook in the freezer for 10 min. Of course, I get 8 gb.

    So what the ****?

    I have gone through every thread google has to offer. No solution, except that the best explanation was that circuit board was getting old. It explains why Apple created new vents for the new Macbooks. I also believe they soldered in the ram for this exact reason.

    So I got sick of it and opened up the macbook, unscrewed, removed, cleaned out the fan, unscrewed the circuit board removed the Ram. I even unscrewed the 4 screws around the plastic RAM holder. I cleaned everything out with 91% isopropyl alcohol and everything inside the RAM holder and the ram itself.

    I tested each RAM in each slot alone and carefully turned the computer on. 4 gb as expected. Both banks worked. Both RAM functioned fine alone in each of the banks.

    So what the ****?

    I popped both back in.....8 gb. Restarted it. 8 gb. I did this 10 x. Every time 8gb.

    So I thought it was because I did a great "cleaning" job. I screwed everything back in, circuit board, RAM "holder", etc. Restarted....7.75 gb. !?

    Restarted again.... 4gb?! DId this 10x, 4 gb.

    What the ****?

    I opened everything and LOOSENED the four screws around the Ram HOLDER.....

    8 gb ever since!

    I believe with time, the awesome heat from the macbook pro eventually warps the circuit board. My macbook was just under 3 years old and started to have this problem. The four screws holding the ram holder in start to tighten up with heat and somehow it does not recognize one bank. That's why when I freeze the macbook, it gets the other bank back. By loosening the screws, it allows the circuitboard expansion with heat.

    Anyways, I hope that helps.
  17. PrimoSlate macrumors newbie

    Apr 3, 2013
    You sir, are a genius.

    I've been fighting with this issue for months. I even had apple replace my logic board, as per their recommendation for a mere $300.00 -- I was just about to take it back to apple when I came across your reply, quadturbo.

    I can attest to this being a solid solid solution for the described issues. (1. Unavailable RAM, usually half and 2. not waking after opening lid, having to force reboot.)

    Thanks again for sharing, mate.
  18. imyselfandi macrumors newbie

    Feb 15, 2012
    As the other post said, you are a genius. I would never have thought of this. I opened up my Mac, removed the logicboard, cleaned everything, replaced the heat sink paste, reinstalled the operating system... you name it. Nothing worked. I thought it might be my optibay or SSD drive. Then I loosened the screws as described. It now wakes from sleep normally. What a relief - I can't thank you enough!
  19. ironflippy macrumors newbie

    Jun 11, 2009
    I've been having the same problem for the past year or so. Just loosened the screws. If this works, then I owe you a hundred beers, this has been such a headache.
  20. jesse12345 macrumors newbie

    May 23, 2013
    Created an account to come here and say that loosening the screws worked for me. I can't thank you enough quadturbo. This has been the biggest headaches for over a year now, and I can't believe it's finally fixed.
  21. Spikeefix macrumors newbie

    Nov 17, 2010
    Wow, thanks for the geniuses here! I have had this exact problem, and I look forward to getting it fixed when I get home. Do Apple Geniuses know about this, because I just took it in to the store and it's continued having problems since then.

  22. Spikeefix macrumors newbie

    Nov 17, 2010
    Thanks. This worked. Two Geniuses at Apple couldn't figure it out, but this worked like a dream. Good Grief, Apple, come on!

    Thanks again, quadturbo!
  23. shervie macrumors newbie

    Jun 8, 2013
    I literally made an account just to thank you! THANK YOU!
    I've had this problem for over 2 years now on and off. I had lost hope. I'm not even sure why I even bothered looking again but I'm glad I came across your post quadturbo. Really Appreciate it.
  24. KUguardgrl13 macrumors 68020


    May 16, 2013
    Kansas, USA
    I have to wonder if this will fix my issue as well. I have a mid-2009 13" MBP that still has the original RAM. I've never upgraded or changed the RAM, but I have had the sleep issue as described above. I haven't seen any issues with disappearing RAM yet. Nearly every time I've taken my machine in, they've replaced the hard drive cable (often the hard restarts from the sleep issue led to the question mark folder or the planet on startup). So I guess I should give this a shot and see if it works! I've been thinking about upgrading the RAM and certainly want it to work!
  25. polymersayb macrumors regular

    Dec 12, 2012
    The screw-loosening didn't work for me unfortunately. In case it doesn't solve it for anyone else, the thing I've had the most luck with is simply to be extra gentle with the laptop. I've noticed I have a tendency to slide my laptop into my bag, and it hits with a little bit of a thud—I think that might be enough to loosen the RAM from the slot and cause all the symptoms above. I've been able to get a week of uptime, and up to 13 days, using that method, and loosening the screws didn't improve on that.

    Hopefully this helps someone out. Lucky for me, I need to upgrade anyway because my computing needs have increased drastically lately (which makes a logic board replacement even less worth it) but I know not everyone has that option.

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