locked
Difference between x86 and x64 ?

    Question

  • Hi,

     

    I want to Know the Difference between x86 and x64 ?

     

    When i say i want to complie my code for Vista 64 bit, what does that mean ?  x86 or x64 ?

     

    Regards

    Kulvinder Singh

    Friday, June 08, 2007 2:31 PM

Answers

  • Kulvinder:

     

    There are a few things that you may be asking with this question. Smile 

     

    Are you asking about the technicial differences between X86 and X64 chip sets?

    http://www.amd.com/us-en/Processors/TechnicalResources/0,,30_182_739_7044,00.html

     

    Are you asking about the differences in PE layouts (PE32 - 32bit, PE32+ - 64bit)?

     

    Or are you asing about about X86, X64 and MSIL (agnostic) managed assmeblies?

     

    I will assume that it is the latter.  Managed assemblies by default are built agnostic so they will run against the native bitness of the platform.  For example, an agnostic assembly running on Vista 64 will run as a 64bit process.  You can also target X86 by running on the WOW (Windows on Windows64) subsystem.  All x86 applications, including X86 managed applications, can run on Win64.

     

    The decision to use 64bit or 32bit is application specific.  Some of the determining factors are: what resources it uses (32bit COM objects, ...), certain performance characteristics, additional address space (64bit), etc.

     

    Hope that this was helpful.

     

    Jeff

    Friday, June 08, 2007 5:33 PM