32-bit or 64-bit - What Is My Processor?
Almost everything you can buy in the server market these days is 64-bit capable - whether AMD or Intel. Almost.
Much of what you buy in the desktop market is 64-bit capable - whether AMD or Intel. Much.
Why do you care? Exchange Server 2007 is only supported in production on 64-bit servers running 64-bit versions of Windows Server 2003 (and soon Windows Server 2008). However, 32-bit versions of Windows Server 2003 can also be installed on 64-bit hardware. And that doesn't count! You need a 64-bit OS to make Exchange Server 2007 happy!
So, if there is any question in your mind about whether your hardware can support a 64-bit operating system, this is how you find out!
In PowerShell, it's easy. Here is a sample:
PS C:\>gwmi win32_processor | fl AddressWidth,DataWidth,Architecture,Manufacturer,MaxClockSpeed
AddressWidth : 32
DataWidth : 64
Architecture : 9
Manufacturer : AuthenticAMD
MaxClockSpeed : 1900
PS C:\>
The most important value here is the Architecture property. A value of 9 is "x64". A value of 0 is "x86" and a value of 6 is "Itanium". There are other historical values (Alpha, MIPS, etc.) but current versions of Windows don't run on those processors. This sample is an x64 processor.
This sample is from my laptop. To decode it a little bit, we see an AddressWidth of 32. This defines the width of a pointer variable for the currently loaded operating system. This tells you that I'm running a 32-bit OS (Windows Vista, in this case).
The DataWidth value of 64 tells you how wide the bus is that moves data into the processor. It also is the maximum possible value for AddressWidth. If a 64-bit OS is loaded, AddressWidth and DataWidth are both 64.
My laptop processor is from AMD, and is a dual-core processor. Each processor has a maximum clock speed of 1.9 Ghz.
Intel processors have "GenuineIntel" for the manufacturer field.
To summarize: you need an Architecture value of 9 and a 64-bit version of Windows Server 2003 installed to be able to install Exchange Server 2007 (for production use!).