Set up your Windows operating system.
Set up your Windows operating system.
Normally, if you have less than 4GB of Memory, you will want 32bit, simply because it uses less RAM than 64bit (1GB compared to 2GB). If you have more than 4GB, you will need 64bit, no other choice about it. Otherwise you won't be able to use more than 4GB.
You purchase the retail box containing Windows, either an upgrade or a full version, which includes two disks—one 32-bit and one 64-bit. Each disk is clearly marked to indicate its type. During installation, there’s no clear sign until the operating system is fully installed. Make sure you select the appropriate disk. If you obtain the OEM version of Windows, you’ll have one disk, depending on whether it’s 32-bit or 64-bit. Choose 32-bit Windows if your system has limited memory, or if your CPU is strictly 32-bit (noted as rare). It seems unlikely you have 2GB of RAM, so opt for the 64-bit disk instead.
I am starting from a USB drive because my new case lacks an optical drive. During setup, I added the 64 Bit version to it. The Windows 8.1 Pro key I purchased indicates it is 64/32 bit. Does that imply it will automatically download the 64-bit version?
The key can trigger either a 32 or 64-bit installation. Because you installed a 64-bit version onto a USB drive, it will initiate the 64-bit setup. But if you had a 32-bit version, it would have started with 32-bit. TL;DR: The key functions properly no matter the original version