2.2. What Are the Advantages?

Why the big push to 64-bit by Microsoft for its server operating systems? Is it just the memory limitations of 32-bit, or are there other compelling reasons? In our opinion, there are four compelling reasons to use 64-bit for servers: memory, performance, security, and virtualization.

2.2.1. Memory

The 32-bit versions of Windows Server use a flat memory addressing scheme, limiting them to a 232 address space. This means a virtual memory address space of only 4 GB, which is divided into 2 GB of virtual memory address space for the operating system and 2 GB of virtual memory address space for applications.