Finally upgrading to Windows 7—should I go 32- or 64-bit?
 

Short answer: 64-bit.

Long answer: 64-bit, but you may not see much real difference. Before explaining why, there is an important contraindication to be aware of: if you use any 16-bit Windows applications or DOS applications, you'll have to either stick with 32-bit Windows, or run those applications in a virtual machine (or, for DOS programs, an environment such as DOSBox). 64-bit Windows supports 64-bit and 32-bit applications, but 16-bit ones are consigned to the trash can of history.

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