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HOWTO: Get Windows 7 to detect your new multi-core processor

Anonymous
2009-12-15T11:11:06+00:00

There is a very rare instance that may happen under Windows 7 if you upgrade

your processor from a single to a dual or a dual to a tri or a tri to quad core processor. Under Windows Task manager > Performance tab you may encounter only the previous amount of cores visible even if you have Task Manager > View > CPU history > One Graph per CPU checked off.

This graph pane area which should show the equivalent amount of cores per graph is directly tied into the MSConfig > Boot tab > Advanced options > "Number of Processors" setting. You may not show the correct amount of cores in this MSConfig pull-down.

Let me give an example:

You install Windows 7 with a dual-core processor and have this option checked for "Number of Processors" (in Msconfig > Boot > Advanced options) and the amount set to "2" (for dual core). This setting is not mandatory to be set but some ppl do in order to force Task Manager to show 2 graphs (or 3). One graph for each processor. At a later point in time you upgrade to a Quad-core or Tri-Core processor. The OS will not read this extra core or have anything enabled to physically use this extra core(s) until the following are performed:

  1. Uncheck in MSConfig > Boot tab > Advanced Options > "Number of Processors" and exit MSConfig
  2. d/l and install an applet called EasyBCD 1.7.2 (or later, Google: EasyBCD) which supports many features of Windows 7.
  3. Go into Advanced Options in EasyBCD and select "Limit Widows to '0' CPUs (Leave 0 to reset)". Click "Apply Settings" and exit EasyBCD.

NOTE: This will force the OS to reset the count to default for the amount of Cores you now have. There is possibly a boot setting that can be added that I may not be aware of to do this same function but this little applet works and does the same thing. Don't muck around with any other setting in this utility if you don't know what you are doing it may leave your computer unbootable and a complete reinstall or long repair may need to be performed. Just make sure this one setting is set to "0"

  1. Completely shutdown the OS (not reboot or restart or logout). Correctly Shutdown you computer so the it powers down.
  2. upon restart into the OS the Task Manager > Performance tab should now show the correct amount of per core graphs if you have the "One Graph per CPU" option selected. Yay your back in business =)

Notes: Some of these discrepancies will appear if your OS is reading the incorrect amount of cores.

  1. Device Manager will show the correct amount of Cores for the PC after the new CPU is installed even tho Task Manager still shows the old amount of cores. This is why you need to preform these steps above to fix this disparity and enable the OS to work with the new additional core.
  2. CPU-Z (Google: CPUID CPU-Z) will show an incorrect amount of cores until you preform the above steps.
  3. SiSoft Sandra (Google: SiSoft Sandra) will show the correct amount of Cores for the PC after the new CPU is installed even tho Task Manager still shows the old amount of cores. This is why you need to preform these steps above to fix this disparity and enable the OS to work with the new additional core.
  4. Reinstalling Windows 7 with the "Upgrade" (not Custom Option) will not fix this issue until the above steps are performed. The reinstall should clear the "Number of Processors" setting in MSConfig but it doesn't! Hence the need to run the above steps and avoid a reinstall which takes greatly more time and still does not fix this issue.
  5. In a dual boot (XP/Win7) PC, the XP Task Manager will show the correct amount of Cores in Task Manager > Performance tab even tho the same place under Windows 7 will not! Hence the need to perform the above steps.

This is a rare issue, but if you are upgrading CPUs in the future these are a very important steps to enable your Win7 OS to take advantage of this extra core you are buying. Even tho in places like Device Manager it will show the correct amount of cores the MSConfig setting will override the Device Manager only allow you to work with a lessor amount of cores thereby limiting your CPUs true potential preserving your good investment.

Good Luck! I hope someone who encounters this issue finds their way here after a CPU upgrade or they may rip their hair out and I can tell you from experience I was making the Level 3 tech support at Microsoft rip their hair out when I found this issue lol

I was getting an Experience Index value for Processor of 6.3 when this core was disabled and not showing up in Task Manager > Performance tab. Once the above steps were performed my Performance Index jumped to 6.9! My old Dual-Core CPU was an Experience Index of 6.1 to show you the difference a 3rd core can add to your system. In the future, once I start gently Overclocking my new Triple-core processor (once I get a better CPU cooler) It should exceed 7.2-7.4 or greater Experience Index. =)

TCsenter wrote also:

Some recommendations (make sure you are running as Administrator):

  • Run MSConfig -> Change to Boot tab -> Advanced Options -> "Number of Processors", make sure there is no check mark.
  • Delete processor entries listed in Device Manager, then reboot and allow Windows to redetect/reinstall them.
  • In BIOS, check for an option named Max CPU ID Value or CPU ID Max Val and make sure its set to disabled .  This option is only provided for OS prior to Windows 2000.  Save and Exit BIOS.
  • Check for a BIOS update for your system or motherboard.
  • Confirm the CPU model is supported by the motherboard
Windows for home | Previous Windows versions | Devices and drivers

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  1. Anonymous
    2011-11-23T00:37:13+00:00

    That is TOTAL C R A P, Windows home premium is fully capable of supporting multi-core processors natively in either 32 or 64 bit install. Whomever told you this you need to call them back and tell them to go to school cause they are full of C R A P.

    I will direct you to the Windows 7 System Requirements.  Perhaps it's you that needs to "go to school because you are full of C R A P"?  The poster you responded to, specificaly stated that he had two [physical] dual-core CPUs.

    Quote:

    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.

    2 dual cores would still be considered a quad not "2 duals" but this is just a semantic and no sense beating a dead horse, so to speak.

    No, they're completely different.  If you have an 8 cylinder car, is that the same as a car with 2 4 cylinder engines?  Heck no.  This is much the same matter.

    2 people found this answer helpful.
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  2. Anonymous
    2010-05-12T17:20:33+00:00

    Okay everyone... ***HERE'S THE CORRECT ANSWER - PERIOD!!!!***And this *HAS* been verified by one one of the project managers involved in Windows 7.

    Windows 7 Home Premium will **ONLY*** show multiple processors IF THE FOLLOWING IS TRUE :

    Your machine has:

    ****** ONE (1) PHYSICAL processor that is a multi-core processor. ******IE: Duo-Core Intel Processor. Some of the HP Laptops that are out now are Quad-Core, ONE PROCESSOR, so that's why W7HP shows 4 processors.

    MORE THAN ONE PHYSICAL PROCESSOR, Windows 7 Home Premium will ***NOT*** support it - PERIOD! W7HP will *ONLY* see the 1st processor & the core(s) of that one ONLY!

    I installed Windows 7 Ultimate and right off the bat, without doing a thing, my machine showed 4 processors, where W7HP only showed 2. That's when I talked to one of my old customers about the issue, and he said Microsoft did this in order to keep business and other people from purchasing W7HP to run on Multi-Processor machines, without spending the additional money, and because W7HP was designed as a "low cost" entry level Windows 7 platform!

    So for those on here that are having this issue, you need to figure out if your machine has ONE PHYSICAL processor with multi-cores, or if it's like mine with MORE THAN ONE PHYSICAL processor. If you only have one, then I would take "passionfly1"'s advice and get Microsoft involved if you are still within your time period. If you have MORE THAN ONE PHYSICAL processor inside your machine, you will have to upgrade to at LEAST Windows 7 Professional in order to utilize more than one physical processor. This is true for BOTH 32 & 64bit versions.

    Hope this helps out a bit!

    2 people found this answer helpful.
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  3. Anonymous
    2009-12-15T21:30:04+00:00

    There is a very rare instance that may happen under Windows 7 if you upgrade your processor from a single to a dual or a dual to a tri or a tri to quad core processor. Under Windows Task manager > Performance tab you may encounter only the previous amount of cores visible even if you have View > CPU history > One Graph per CPU checked off.

    ...

    ..

    .

    I was getting an Experience Index value for Processor of 6.3 when this core was disabled and not showing up in Task Manager > Performance tab. Once the above steps were performed my Performance Index jumped to 6.9! My old Dual-Core CPU was an Experience Index of 6.1 to show you the difference a 3rd core can add to your system. In the future, once I start gently Overclocking my new Triple-core processor (once I get a better CPU cooler) It should exceed 7.2-7.4 or greater Experience Index. =)

    Hey Peter,

    Thanks for uploading it here and bringing this to MS's notice as well this shall be looked into.

    Many thanks once again!

    MS Supoort

    2 people found this answer helpful.
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  4. Anonymous
    2012-06-12T17:21:20+00:00

     

      I would trust TYAN support far more than Microsoft.

    thats why im here.  the last no speaking English person didnt know they were working for microsoft.

    Hello...

         The three basic versions of win 7 supports single processors with multi-cores.  Win 7, in those classes,   will not recognize  2 physical processors .. only "pro" and beyond for some obscure greed based reason.   I hope they patch this injustice to humanity. 

         I have two "physical" XEON 3.2 processors and did not recognize this fact till after I ran passmark.  A quick google of MS WIN 7 requirements  or a search at MSDN will verify.

    http://windows.microsoft.com/en-US/windows7/products/system-requirements

    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.

    http://windows.microsoft.com/en-US/windows7/products/system-requirements

    1 person found this answer helpful.
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  5. Anonymous
    2010-04-20T05:40:06+00:00

    Some recommendations (make sure you are running as Administrator):

    • Run MSConfig -> Change to Boot tab -> Advanced Options -> "Number of Processors", make sure there is no check mark.
    • Delete processor entries listed in Device Manager, then reboot and allow Windows to redetect/reinstall them.
    • In BIOS, check for an option named Max CPU ID Value or CPU ID Max Val and make sure its set to disabled .  This option is only provided for OS prior to Windows 2000.  Save and Exit BIOS.
    • Check for a BIOS update for your system or motherboard.
    • Confirm the CPU model is supported by the motherboard

    thank you for this update. I did not have this BIOS setting. I will add this tidbit to the original post.

    1 person found this answer helpful.
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