A. Microsoft has released all versions of Windows Vista as both 64-bit and 32-bit, except for Windows Vista Starter Edition, which is 32-bit only. Windows Vista Basic 64-bit supports up to 8GB of RAM, Home Premium supports up to 16GB of RAM, and the Business, Enterprise and Ultimate versions support up to 128GB of RAM. 4GB is the maximum RAM supported by all 32-bit versions of Windows Vista.

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