The Notebook Review forums were hosted by TechTarget, who shut down them down on January 31, 2022. This static read-only archive was pulled by NBR forum users between January 20 and January 31, 2022, in an effort to make sure that the valuable technical information that had been posted on the forums is preserved. For current discussions, many NBR forum users moved over to NotebookTalk.net after the shutdown.
Problems? See this thread at archive.org.

    Did your vendor set the /3GB switch on Win XP with 4G ram for you?

    Discussion in 'Sager and Clevo' started by sfxocean, Sep 8, 2008.

  1. sfxocean

    sfxocean Notebook Enthusiast

    Reputations:
    7
    Messages:
    28
    Likes Received:
    0
    Trophy Points:
    5
    Got a Sager 9262, Win XP Pro 32bit w/ 4GB ram, and while configuring a database realized that applications could not see more than 2GB of memory, even though the O/S reports 4GB (minus of course hardware/drivers in the upper memory).

    A quick search of the web turns up this little jewel - by default XP splits the 4GB memory allocating 2GB for the O/S and 2GB for applications. If you want to give your applications 3GB of that memory and leave 1GB for XP, you have to set the /3GB switch in your boot.ini file, and your vendor may not have done this for you.

    Here's an example boot.ini entry, before and after the switch has been added:

    multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect

    multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /3GB

    When you reboot your apps that know how to use more than 2GB ram can have at it...
     
    sfxocean, Sep 8, 2008
    #1
  2. baconcow

    baconcow Notebook Consultant

    Reputations:
    22
    Messages:
    225
    Likes Received:
    0
    Trophy Points:
    30
    Interesting. However, I don't think Windows XP will ever be able to use the full 4 GB of RAM anyways. Isn't the cap set at around 3.2 GB? But, I never knew that switch existed.
     
    baconcow, Sep 8, 2008
    #2
  3. Gophn

    Gophn NBR Resident Assistant

    Reputations:
    4,843
    Messages:
    15,707
    Likes Received:
    3
    Trophy Points:
    456
    XP 32-bit can see ~3GB automatically... its may vary a bit depending on the hardware in the system, but there is no real benefit from the switch.
     
    Gophn, Sep 8, 2008
    #3
  4. sfxocean

    sfxocean Notebook Enthusiast

    Reputations:
    7
    Messages:
    28
    Likes Received:
    0
    Trophy Points:
    5
    Yes XP can see, but Oracle can not, until the switch is set... Search the web, this is not for Oracle only, the indication is lots of applications will not use the memory beyond 2G without XP "releasing" it's allocation, and you would not know it unless you were paying attention
     
    sfxocean, Sep 8, 2008
    #4
  5. Gophn

    Gophn NBR Resident Assistant

    Reputations:
    4,843
    Messages:
    15,707
    Likes Received:
    3
    Trophy Points:
    456
    I see.

    I have not worked with Oracle in a while... good to know. :)
     
    Gophn, Sep 8, 2008
    #5