Just about any 64-bit processor you can find on the market is fully capable of running 32-bit operating systems and 32-bit applications. In addition, 64-bit versions of Windows can run 32-bit programs, though they require 64-bit drivers and 64-bit compatible security software.
Hope this helps,
John
If i have a 64 bit processor, is it okay to use a 32 bit version of vista?

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