Results 1 to 10 of 16

Thread: 6 GB RAM is installed, but only 2 GB appears

Hybrid View

  1. #1
    Join Date
    Jun 2006
    Location
    Rio de Janeiro
    Beans
    38
    Distro
    Ubuntu

    6 GB RAM is installed, but only 2 GB appears

    Hi.
    I have a weird problem.
    My computer has 6 GB of RAM, but when I turn it on only 1.7 GB of RAM is available. If I run lshw, I can see that the all the RAM is installed. If I restart the system a few times, all the RAM is recognized properly.
    Does anyone know the reason for this behavior?

    free -m
    Code:
                 total       used       free     shared    buffers     cached
    Mem:          1723        690       1033          0         78        231
    -/+ buffers/cache:        381       1342
    Swap:         9443          0       9443

    sudo lshw -class memory
    Code:
      *-firmware              
           descrição: BIOS
           fabricante: American Megatrends Inc.
           physical id: 0
           versão: P1.40
           date: 12/04/2012
           tamanho: 64KiB
           capacidade: 4032KiB
           capabilities: pci upgrade shadowing cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer acpi usb biosbootspecification
      *-memory
           descrição: Memória do sistema
           physical id: 8
           slot: Placa do sistema ou placa-mãe
           tamanho: 6GiB
         *-bank:0
              descrição: DIMM DDR3 Síncrono 1333 MHz (0,8 ns)
              produto: 9905471-006.A00LF
              fabricante: Kingston
              physical id: 0
              serial: 65206C13
              slot: A1_DIMM0
              tamanho: 4GiB
              largura: 64 bits
              clock: 1333MHz (0.8ns)
         *-bank:1
              descrição: DIMM DDR3 Síncrono 1333 MHz (0,8 ns)
              produto: 9905402-179.A00LF
              fabricante: Kingston
              physical id: 1
              serial: 7E13B005
              slot: A1_DIMM1
              tamanho: 2GiB
              largura: 64 bits
              clock: 1333MHz (0.8ns)
      *-cache:0
           descrição: L1 cache
           physical id: f
           slot: L1 CACHE
           tamanho: 384KiB
           capacidade: 384KiB
           clock: 1GHz (1.0ns)
           capabilities: pipeline-burst internal write-back unified
      *-cache:1
           descrição: L2 cache
           physical id: 10
           slot: L2 CACHE
           tamanho: 3MiB
           capacidade: 3MiB
           clock: 1GHz (1.0ns)
           capabilities: pipeline-burst internal write-back unified
    uname -a
    Code:
    Linux Principal-sala 3.2.0-36-generic #57-Ubuntu SMP Tue Jan 8 21:44:52 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

  2. #2
    Join Date
    Nov 2011
    Location
    /dev/root
    Beans
    7,051

    Re: 6 GB RAM is installed, but only 2 GB appears

    So sometimes, after several reboots, all the memory will be grabbed by Ubuntu!

    - Could it be a bad connection? Move the RAM cards a little, pull out and push in again and check if it helps.

    - Check if you get some error with memtest (that you can start from the grub menu at boot). Run it for a long time, overnight if possible, to catch an error that might show up only once in a while. I suggest that you reboot until your computer (and memtest) will grab all the RAM.

  3. #3
    Join Date
    Nov 2008
    Location
    Metro Boston
    Beans
    8,536
    Distro
    Kubuntu 14.04 Trusty Tahr

    Re: 6 GB RAM is installed, but only 2 GB appears

    It doesn't look like you're using the 64-bit version of the kernel. The 32-bit version cannot address all six gigabytes unless you have the -pae kernel installed, which uname does not report either.

    Try booting from a 64-bit installation CD and run "Try Ubuntu". When it finishes loading, run free again. If you see all your memory, then you should consider upgrading to the 64-bit version.
    If you ask for help, please have the courtesy to check for responses and thank the people who helped you.

    Blog · Linode System Administration Guides · Android Apps for Ubuntu Users

  4. #4
    Join Date
    Nov 2011
    Location
    /dev/root
    Beans
    7,051

    Re: 6 GB RAM is installed, but only 2 GB appears

    Quote Originally Posted by SeijiSensei View Post
    It doesn't look like you're using the 64-bit version of the kernel. The 32-bit version cannot address all six gigabytes unless you have the -pae kernel installed, which uname does not report either.

    Try booting from a 64-bit installation CD and run "Try Ubuntu". When it finishes loading, run free again. If you see all your memory, then you should consider upgrading to the 64-bit version.
    But in post #1 [s]he wrote

    uname -a

    Code:
    Linux Principal-sala 3.2.0-36-generic #57-Ubuntu SMP Tue Jan 8 21:44:52 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
    which indicates a 64-bit kernel (x86_64)

  5. #5
    Join Date
    Nov 2008
    Location
    Metro Boston
    Beans
    8,536
    Distro
    Kubuntu 14.04 Trusty Tahr

    Re: 6 GB RAM is installed, but only 2 GB appears

    Sorry, I guess I didn't scroll right far enough.
    If you ask for help, please have the courtesy to check for responses and thank the people who helped you.

    Blog · Linode System Administration Guides · Android Apps for Ubuntu Users

  6. #6
    Join Date
    Dec 2007
    Beans
    10

    Re: 6 GB RAM is installed, but only 2 GB appears

    Given that you have to restart a few times to have it detected properly...

    Do this: Pay attention to the BIOS memory check screen, and see if it's detected properly there. To make the BIOS screen stay longer, turn off quick memory check. If yes, run Memtest86 whenever you notice the BIOS detecting less RAM than installed.

    If no, then I'd suspect either RAM not seated properly, bad RAM, or (sometimes) PSU too weak to drive that many bars of RAM.

    If yes, however, it may be a quirk with the firmware. Try upgrading your firmware and see if the problem goes away.

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •