When 4 = 3

I just built a new machine and loaded it up with RAM to 4 GB. Little did I know that I would need a 64 bit version of Windows to use it all. After all 32 bits allows for 4 GB of address space, and the Microsoft web site says Windows 32 bit can handle up to 4 GB. But in most cases, if you want to use more than 3 GB of RAM, you will need to use a 64 bit version of Windows, and even then you may still be stuck at around 3 GB depending on your hardware (Even if it says it supports up to 4 GB).  More