Vista Mythbusters #2: Dual-core and 64-bit support

Vista Mythbusters #2: Dual-core and 64-bit support

Summary: Will Windows Vista support dual-core CPUs? How will 64-bit Vista versions be delivered? Get the answers in the latest installment of my Vista Mythbusters series.

TOPICS: Windows

This is the second in my series on Vista myths. A pair of questions keep popping up in the Talkback section whenever I write about Windows Vista, so let's deal with them right now.

Myth: Some versions of Windows Vista won't support dual-core CPUs or 64-bit processors.

Reality: Every Vista version supports dual-core processors, and every version is available in a 64-bit native version as well.

Part of the confusion rests with the specifications for some fairly exotic hardware. If you have a PC with multiple physical CPUs - that is, two or more chips installed on the motherboard - you'll need Windows Vista Business, Enterprise, or Ultimate to take advantage of both CPUs. If you install Vista Home Basic or Home Premium, the OS will only recognize one CPU. That's similar to the way Windows XP works today - if have a dual-CPU machine, you need to install XP Professional to use both CPUs.

So what about dual-core CPUs? That's different. All Vista versions, even the lowly Home Basic, support multiple cores on a single chip, with no additional configuration required.

Update 13-November: Don't just take my word for it. Before dual-core chips reached the market, Microsoft publicly declared that its definition of processor encompasses physical CPUs, not individual cores:

On October 19, 2004, Microsoft announced that its server software that is currently licensed on a per-processor model will continue to be licensed on a per-processor, and not on a per-core, model. This policy will allow customers to recognize more performance and power from Microsoft software on a multicore processor system without incurring additional software licensing fees.


The story with 64-bit Windows is a little more complicated. Today, Windows XP Professional is available in separate 32-bit and 64-bit versions that are functionally identical but must be purchased separately. In Vista, every version will be available in both 32- and 64-bit versions. A Microsoft spokesperson tells me they're still working out the details, but the current plan is to include 32-bit versions in retail packages; if you want to install a 64-bit version, you'll have to call and request that the alternative media be sent to you. The same spokesperson says Microsoft may include both 32-bit and 64-bit DVD media in the Windows Vista Ultimate box. For $399, that sounds like the right thing to do.

Previously in this series:

Vista Mythbusters #1: It's not a hardware hog

Topic: Windows

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  • This dual core processor talk always confuses me


    When I go to Device Manager and look under Processors, it lists two separate processors. But despite what it says, I think I have only physical processor in this machine. How do I know for sure? Would it help if I e-mailed you a screen shot from Device Manager?

    • No need to e-mail a screen

      Believe me, you would know if you had two separate physical CPUs, because the invoice for your PC would be about $500-1000 more! Dual-CPU machines are very rare.

      Try running Msinfo32.exe. In the System Summary section, look for the Processor entry. It should tell you how many cores, how many logical processors, and how many physical processors you have.
      Ed Bott
      • Well, I looked at the System Summary section...

        ...and it shows two processors. It doesn't tell me how many cores, logical processors, or physical processors. Just two processors, each with the identical name.

        This is an expensive, high end PC. It runs like a bat out of hell. If I had to guess, it would be one CPU with two logical processors. But how can I KNOW? I am as befuddled as ever. And very curious. :)
        • Should give you processor specs

          Interesting. I only have XP on single-CPU systems and Vista on dual-CPU, so I can't tell easily.

          But you should be able to look any number of places and see a diagnostic display showing the actual processor specs. Maybe in the BIOS setup, maybe using the Msinfo32 tool. Maybe using Belarc Advisor. What does it show as the name of each processor?
          Ed Bott
          • just take a look

            If you open the side of your case you'll be able to see if there is one or two processors in it right away.
          • I did some further checking

            Thanks. I ended up downloading a utility from Intel that identified the processor as a Pentium 4 570 3.8 GHz. According to Intel, it is not a dual core processor. [Insert "dang" here.] It does have hyperthreading capability, which may explain why Device Manager, Task Manager, and System Manager all report "two" processors.

            Incidentally, XP Device Manager reports the name of "both" processors simply as "Intel Pentium 4 CPU 3.80 GHz." System Information calls "them" x86 Family 15 Model 4 Stepping 1 GenuineIntel ~3801 MHz."
          • indeed its hypertreading

            it appears as two separate cores to the OS...
          • Galileon, thanks...

            ...for confirming that for me.
          • No Dual Processors with Pentium 4

            I don't believe there are ANY dual processor systems using Pentium 4 processors. I had a dual processor Pentium 3 system - still do actually. But for some reason, something to do with the way the Pentium 4 cpu is made prevents or discouraged motherboard makers from making dual processor motherboards for the P4.

            You do have hyperthreading though, which is very similar to dual core. This is why the Device Manager shows 2 processors. Hyperthreading lead up to Dual Core. So, you have 2 threads working within the same physical processor (2 threads = 2 virtual processors), just as any Dual Core processor would do. Your P4 processor multi-tasks! And that's good.
          • The mystery may be solved

            Thanks. Yes, I definitely have hyperthreading. And as I told Ed, this thing runs like a bat out of hell, even when I deliberately stress the system.
  • And, the biggest Vista myth of all??

    That there would be any reason for companies and individuals to use it, of course.

    Stay with XP for now and slowley reduce your dependency on Windows programs that are costing you lots of money, and of course all of the security headaches. At some point the switch to Linux will be a no brainer, but be patient.

    And, the virus writers have to be loving the millions of lines of new code in Vista that can be exploited together with the existing rats nest left in for backward compatibility. Well, they won't release any exploits until there is a critical mass on Vista. That might be a few years out, if ever.
    • The biggest myth of all - Donnieboy

      I'd think you were a badly put-together spambot, but they usually have better grammar and spelling.

      How you gonna keep em down on the farm after they've seen Paris?

      De-evolution, that's what we're talking, back to the root <pun>. Let's go back to simpler times, less choice, less options, less features, less apps, no games and make Donnie our best friend.

      What you don't see the advantages? Throw away all the powerful apps, there's mickey mouse Web 2.0 and all those wonderfully clunky *nix apps to choose from.

      Don't stop with Linux - bring back DOS. I don't think virus writers can do assembler any more.

      In fact - let's go clay tablet and stick - that'll stop those virus writers.
      • Message has been deleted.

        • Linux Am Be Good, Then?

          IQ high is mine, so choose Linux I?
      • VicFung

        Be careful about criticizing an innocent spambot's grammar. It should be:
        fewer options, fewer features, fewer apps

        not "less options, less features, less apps"

        as you have written.
      • Tony, slapping DonnieBoy with truth and facts

        is a pure waste of time. He found his religious calling.
        • Hello Pot!!!!

          Have you met the kettle.......?
          Spoon Jabber
        • Yes, but...

          ...does he have to preach it to the rest of us??
      • I agree!

        Oh Donnieboy is afraid to venture out it seems. That's okay - there are many folks like him to support his point of view.

        Donnieboy believes we are 2 digit IQ Windows users. I personally believe there are very few - one does need to understand what they want to use Windows or a computer for - the vast majority of humans are far within the 3 digit IQ range, many with IQ's far beyond that of Donnieboy. :)
      • You are a Windows using Dinosour Tony

        Linux-BSD-Mac are light years ahead of Windows. When did you last try Linux. 10yrs ago. Not one of your Linux put down applies today.

        Less apps- Ubuntu has thousands of pre approved ready to go apps

        Less choice- Linux has 50 X as much choice in which you can say install as little as floppy all the way to a dual DVD install. You have several GUI running on several levels of hardware so your hardware is never obsolete.

        Windows is the obsolet OS with an obsolete file system. Apple new that they had to move forward with a Unix style system. Microsoft and their users are the ones that refusing to get with the new times.

        Microsoft and their users are holding back the advance in the PC industry.