Comparison 64bit vs 32bit

I notice that for most people, it's still a big question what are the most important differences between 32-bit and 64-bit.  I hope this table will help you understand why 64 bit os better, and why it doesn't have to be that more expensive. 

General Memory Limits 32-bit 64-bit 
Total Virtual Address Space 4 GB  16 TB
Virtual Address Space per 32-bit process 2GB (3 GB if system is booted with /3gb switch) 4GB if compiled with /LARGEADDRESSAWARE 2GB otherwise
Virtual Address Space per 64-bit process Not applicable 8 TB
Paged Pool 470 MB 128 GB
Non-Paged Pool 256 MB 128 GB
System PTE 660 MB - 900 MB 128 GB
Physical Memory and CPU Limits  32-bit 64-bit
Windows XP Professional 4 GB / 1-2 CPUs 32 GB / 1-2 CPUs
Windows Server 2003 Standard Edition  4 GB / 1-4 CPUs 32 GB / 1-4 CPUs
Windows Server 2003 Enterprise Edition 64 GB / 1-8 CPUs 1 TB / 1-8 CPUs
Windows Server 2003 Datacenter Edition 64 GB / 1-32 CPUs 1 TB / 1-64 CPUs

Source: ePact.

Comment List
Related
Recommended