Choosing Between Windows Vista 32-bit and 64-bit Editions

Historically, the 64-bit edition of Windows XP hasn’t been a runaway hit. It’s not really surprising in many ways: the x64 version was a rather specialist product built off the Windows Server 2003 codebase, which traded a loss of support for a number of features (including .NET Framework and DirectX in early releases) in return for the ability to address vast amounts of memory from a single process. Since the AMD64 and Intel EMT64 ranges of processors happen to run 32-bit code extremely quickly, it’s not surprising that even though probably the majority of machines sold these days are 64-bit capable, they are running the standard 32-bit version of the Windows XP operating system, with the 64-bit edition used mostly for workstation-class tasks such as engineering and scientific applications.

In Windows Vista, the choice becomes far more pertinent for most people. Gone are the limitations of the 64-bit edition in terms of what software comes shipped with the operating system: a “Longhorn Basic” requirement for any feature to have been accepted into the operating system was to be supported on both 32-bit and 64-bit platforms. But the 64-bit version also takes advantage of the hardware to offer some attractive security features that are exclusive to that platform. On the downside, you’ll still see weaker downlevel compatibility on the 64-bit platform: for example, we don’t support 16-bit code from the Windows 3.x days (which is a little more of an issue than many people realize due to the inclusion of 16-bit code in the installers for some decidedly 32-bit applications).

The choice is an interesting one, and by far the best article I’ve seen explaining the differences between the two platforms in detail is from Paul Thurrott’s Windows Supersite. It succinctly defines the pitfalls and strengths of each choice. It’s also worth checking out the Windows Vista Product Guide for more details. I’m considering holding out for one of the new Merom-based notebooks that will contain dual-core, hyperthreaded 64-bit processors: so much power in one portable machine that it makes me drool!

Comments (91)

  1. PatriotB says:

    So based on your "Longhorn Basic" sentence above, I’m assumg that in x64 Vista will include 64-bit components of Windows Media Player (as well as the 32-bit)?  I had some programs that I wrote that used the WMP ActiveX control and tried making 64-bit versions for the heck of it, and was surprised that XP x64 didn’t include 64-bit versions of the WMP controls.  Looks like that’s finally been fixed.  (Though with WMP, I’m guessing the default end-user app will still be the 32-bit version for the same reason the IE default is 32-bit: compatibility with plugins/codecs…)

  2. Anonymous says:

    I think you miss reason #1 why 64-bit XP isn’t a runaway hit:  Driver support.   So few devices have 64-bit drivers for XP that it’s quite difficult to use any of your old (or new!) devices in it.  And since so few people ran 64bit XP, manufacturers didn’t create drivers.  

    Since many drivers are being re-written or updated for Vista, manufacturers will hopefully (and seem to be) also make sure to allow for 64bit capability at the same time.  If so I can see a huge surge in 64bitness…. maybe all the OEMs shipping x64 systems will put a 64bit OS on it!

  3. Anonymous says:

    Merom is not hyperthreaded but I am definitely waiting to get one to take x64 Vista for a drive

  4. Anonymous says:

    Drivers for Vista are backwards compatible with XP, meaning that if you have XP x64, that the driver problem is all but gone. There’s a few things I didn’t see him mention, like that XP x64 will be cheaper, supports 128GB ram already, has fewer compatiblility issues with 32 bit programs, and offers more security than normal XP. So why upgrade to the system Hog that Vista will be when you could just boot XP x64?

  5. Anonymous says:

    Since 64-bit processors can run 32-bit code, will Vista 64-bit run 32-bit apps out-the-box?

  6. Anonymous says:

    I didn’t really have a problem with drivers for XP64, and haven’t had any issues with the Vista64 beta either.  Sound and Chipset drivers were nVidia supported, as well as video.  I even have SATA RAID running native 64 bit drivers, or at least drivers that Vista recognizes as being made for the hardware.

    Everything runs rather well, and for Beta2 I’m very surprised.  I didn’t accept XP64 until it supported SLi for games, and once it crossed that bridge, it’s been 64 all the way.  It works much better in so many respects due to the 64 bit drivers.

  7. Anonymous says:

    I am pretty sure that all of my 32-bit apps that DO run on the x86 Vista Beta2 also run on my x64 Vista Beta2.  I haven’t tried ALL of them yet, but haven’t found any differences so far.  This is also the case when running XP Pro x64.  It simply recognizes that it’s a 32-bit app and runs it accordingly.

  8. Anonymous says:

    As for XP x64 running SLI:  I haven’t had a problem with that since SLI became available.  It does NOT, however, work in Vista Beta2 as of yet.  (Unless nVidia has released a new driver since yesterday…)  It is the one thing I wanted to see if Vista will be supporting in a native way for us gamers.  I haven’t tried it on the Beta2 x86, so I’m not sure, but I know that everything was a bit weird to not have my SLI functioning in the x64 Vista Beta.

  9. Anonymous says:

    I’ve been running XP64 since t least last Xmas, and I love it, everything I need runs like a dream, just wondering now about Vista 64, which I’ll prolly install just cos i can 🙂

    Definately recomend XP64 to anyone that can run it.

  10. Anonymous says:


    I have successfully Ghosted Windows Vista 64 with Ghost 2003.  The problem some may have encountered is not with Ghost but rather with the combination of SAT and PAT type drives.  To see both types of drives you must make changes to the ghost.ini file.


    I hope this helps,

    Rick Johnson

  11. Anonymous says:

    While searching for articles regarding which to install for Windows XP (64 or 32 on this new computer I’m building), this blog post helped me out.  I appreciate that!  Thank you 😀

  12. Anonymous says:

    Dentists don't bother me. Due to an absence of nerves, they can repair my mouth and teeth without