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Mac Pro  March 2009 dual quad core only recognizes two processors

2155 Views 9 Replies Latest reply: Sep 14, 2013 5:54 AM by Csound1 RSS
ProImagesPa Level 1 Level 1 (65 points)
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Jan 28, 2011 5:54 PM
I installed Win7 Professional 32 bit. I realize now that I should have bought the 64 bit version. The problem with the 32 bit is that it only recognizes two of eight processors and two of eight gigs of Ram.
My questions are:
1. Which 64 bit version should I buy?
2. Will it recognize all eight processors?
3. Will it recognize all eight gigs of RAM, two on each processor?
4. How should I go about uninstalling Win7 32 bit and installing Win7 64 bit?
Mac Pro '09, Mac OS X (10.5.6), 17" MBP, 24' IMac
  • Jaygyver Level 3 Level 3 (725 points)
    If you have "DUAL" quad Proc's then why would you see more then TWO.:)

    It just means you have 4 "CORES" -PER- processor. Think of the "Cores" as 4 "mini" processors in each individual processor. Does your Mac OS show more then 2 processors when you go to "About This Mac"/"More Info"?

    The ram is not "assigned" a processor, it's used by ALL the programs in a "as needed" basis. If your still only seeing 2 gigs+- of ram then it looks like you'll need 64_bit. I only have XP, but I know Windows 7 64_bit shows all your Ram.

    You might ask Microsoft if they have an Upgrade system from 32 to 64_bit.
    Or, use another HD with 2 partitions and use both for compatibility issues.

    64_bit (or 32_bit) only refers to the "basic" Operating System. Windows 7 Home, Pro, etc, just adds more "features" as you go up.
    Be aware though, you will need to find out what devices/applications need to have 64_bit drivers.
    (For anyone looking at Home, you will have to pay another $100 above the Home version to get Pro for the "XP Compatibility Mode".)

    Hope this helps....
    3.2ghz 4 core Late 2110 MacPro., Mac OS X (10.6.6), G4-450 AGP, G4-533 DA, TiBook 550, G3 600 IBook, 6200CD Performa, Apple lle
  • Fortuny Level 7 Level 7 (21,415 points)

    DON'T get the Home version !!

    Home versions of WIndows (XP, Vista, WIndows 7) only support ONE physical processor with multiple cores.

    Only the PRO versions and above support TWO physical processors with multiple cores each.

    With your now installed 32-bit Windows 7 Pro you should see eight bars (= eight cores) when using the Activity Monitor from within the Task-Manager.


    MacPro 2.66 (Late 2006) 8GB X1900XT, Mac OS X (10.6.6), Refurb 27" iMac i7 4GB 1TB iPad Wi-Fi 32GB
  • Fortuny Level 7 Level 7 (21,415 points)

    the 2GB RAM limit is "normal" on a MacPro with 32-bit Windows.

    I have it on my 2006 MP with XP 32-bit as well.

    Using a 64-bit WIndows 7 Professional/Business/Ultimate is the solution to get the full RAM amount and the full processor/cores to work.


    MacPro 2.66 (Late 2006) 8GB X1900XT, Mac OS X (10.6.6), Refurb 27" iMac i7 4GB 1TB iPad Wi-Fi 32GB
  • posimosh Level 1 Level 1 (10 points)

    ^^^ 32-bit means 2 gb of ram is all windows  can utilize

  • The hatter Level 9 Level 9 (58,600 points)

    1.9GB is a 'feature'  of EFI-32


    With later models like 2009 (dual 4-core) that have EFI-64 that surprise to me


    NEVER ever want 32-bit OS today. Ever.


    Home Premium for single socket, Pro for dual, and Pro for more than 16GB RAM. 8GB is actually pretty light for a workstation today for most any type of use.

  • Csound1 Level 7 Level 7 (32,475 points)

    Jaygyver wrote:


    If you have "DUAL" quad Proc's then why would you see more then TWO.:)

    Two 4 core processors = 8 cores, and that is what the 64 bit version will see, 32 bit versions can only use 2 of the 8 cores.


    PCs with multi-core processors:
    Windows 7 was designed to work with today's multi-core processors. All 32-bit versions of Windows 7 can support up to 32 processor cores, while 64‑bit versions can support up to 256 processor cores.

    PCs with multiple processors (CPUs):
    Commercial servers, workstations, and other high-end PCs may have more than one physical processor. Windows 7 Professional, Enterprise, and Ultimate allow for two physical processors, providing the best performance on these computers. Windows 7 Starter, Home Basic, and Home Premium will recognize only one physical processor.


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