1. Windows 98
486DX 66 megahertz (MHz) or faster processor (Pentium central processing unit recommended).
16 megabytes (MB) of memory (24 MB recommended).
A full install of Windows 98 on a FAT32 drive requires 175 MB of free hard disk space, but may range from between 140 MB and 255 MB,
VGA or higher resolution (16-bit or 24-bit color SVGA recommended)

2. Windows me Minimum system requirements: Processor: Pentium 150MHz
Hard drive space: 320MB
RAM: 32MB
Recommended system requirements:
Processor: Pentium II 300MHz
Hard drive space: 2GB
RAM: 64MB

3. Windows NT
Pentium or faster processor 16 megabytes (MB) of memory (RAM); 32 MB recommended
110 MB of available hard disk space
CD-ROM drive or access to a CD-ROM over a computer network
VGA or higher-resolution display adapter
Microsoft Mouse or compatible pointing device

4. Windows 2000 Professional
133 MHz or more Pentium microprocessor (or equivalent). Windows 2000 Professional supports up to two processors on a single computer.
64 megabytes (MB) of RAM recommended minimum. 32 MB of RAM is the minimum supported. 4 gigabytes (GB) of RAM is the maximum.
A 2 GB hard disk that has 650 MB of free space. If you are installing over a network, more free hard disk space is required.
VGA or higher-resolution monitor.
Keyboard.
Mouse or compatible pointing device (optional).

5. Windows 2000 Server
133-MHz or more Pentium CPU. A maximum of four CPUs per computer are supported.
256 megabytes (MB) of RAM is the recommended minimum. 128 MB is the minimum that is supported. 4 gigabytes (GB) is the maximum that is supported.
A hard disk partition that has sufficient free space to accommodate the Setup process. The minimum amount of space that is required will be approximately 1 GB. More space might be needed, depending on the following factors:
The more components you want to install, the more space that you must have.
The file system that is used: FAT requires MB more free disk space than other file systems.
The method that is used for installation: if installing from over a network, allow for MB more space than if installing from the CD-ROM. (More driver files have to be available during installation over a network.)
The size of the paging file.
An upgrade could require much more space than a new installation.
VGA or higher-resolution monitor.
Keyboard.
Mouse or other pointing device (optional).

6. Windows 2000 Advanced Server
133-MHz or more Pentium CPU. A maximum of eight CPUs per computer are supported.
256 megabytes (MB) of RAM is the recommended minimum. 128 MB is the minimum that is supported. 8 gigabytes (GB) is the maximum that is supported.
A hard disk partition that has sufficient free space to accommodate the Setup process. The minimum amount of space that is required will be approximately 1 GB. More space might be needed, depending on the following factors:
The more components you want to install, the more space that you must have.
The file system that is used: FAT requires MB more free disk space than other file systems.
The method that is used for installation: if installing over a network, allow for MB more space than if installing from the CD-ROM. (More driver files have to be available during installation over a network.)
The size of the paging file.
VGA or higher-resolution monitor.
Keyboard.
Mouse or other pointing device (optional).

7. Windows xp home edition
Pentium 233-megahertz (MHz) processor or faster (300 MHz is recommended)
At least 64 megabytes (MB) of RAM (128 MB is recommended)
At least 1.5 gigabytes (GB) of available space on the hard disk
CD-ROM or DVD-ROM drive
Keyboard and a Microsoft Mouse or some other compatible pointing device
Video adapter and monitor with Super VGA (800 x 600)or higher resolution
Sound card
Speakers or headphones

8. Windows XP Professional
Pentium 233-megahertz (MHz) processor or faster (300 MHz is recommended)
At least 64 megabytes (MB) of RAM (128 MB is recommended)
At least 1.5 gigabytes (GB) of available space on the hard disk
CD-ROM or DVD-ROM drive
Keyboard and a Microsoft Mouse or some other compatible pointing device
Video adapter and monitor with Super VGA (800 x 600) or higher resolution
Sound card
Speakers or headphones

9. Microsoft Windows Server 2003
PC with a 133-MHz processor required; 550-MHz or faster processor recommended; support for up to four processors on one server
128 MB of RAM required; 256 MB or more recommended; 4 GB maximum
1.2 GB for network install; 2.9 GB for CD install
CD-ROM or DVD-ROM drive
VGA or hardware that supports console redirection required; Super VGA supporting 800 x 600 or higher-resolution monitor recommended

10. Windows Vista Home Basic
1 GHz 32-bit (x86) or 64-bit (x64) processor
512 MB of system memory
20 GB hard drive with at least 15 GB of available space
Support for DirectX 9 graphics and 32 MB of graphics memory
DVD-ROM drive
Audio Output
Internet access (fees may apply)

11. Windows Vista Home Premium / Business / Ultimate
1 GHz 32-bit (x86) or 64-bit (x64) processor
1 GB of system memory
40 GB hard drive with at least 15 GB of available space
Support for DirectX 9 graphics with:
WDDM Driver
128 MB of graphics memory (minimum)
Pixel Shader 2.0 in hardware
32 bits per pixel
DVD-ROM drive
Audio Output
Internet access (fees may apply)

12. Windows Server 2008
1GHz (x86 processor) or 1.4GHz (x64 processor) • Recommended: 2GHz or faster Minimum: 512MB RAM • Recommended: 2GB RAM or greater • Maximum (32-bit systems): 4GB (Standard) or 64GB (Enterprise and Datacenter) • Maximum (64-bit systems): 32GB (Standard) or 2TB (Enterprise, Datacenter and Itanium-Based Systems)Available Disk Space• Minimum: 10GB • Recommended: 40GB or greater Note: Computers with more than 16GB of RAM will require more disk space for paging, hibernation, and dump filesDriveDVD-ROM driveDisplay and Peripherals• Super VGA (800 x 600) or higher-resolution monitor • Keyboard • Microsoft Mouse or compatible pointing device

13. Windows XP Home Edition
Windows XP Professional Edition
           
User management
Limited to 2 security levels, no policies
Full User Management and Security Policies
            
Workgroup networking/ Joining domains
Limited to Workgroup network (unable to join a domain)
Workgroup networking and able to join a Domain
                
Security on sharing disks and folders
no security, everybody has access to shared data
Full security based on User Management
Limit of simultaneous file-sharing connections
max 5 simultaneous file-sharing connections
max 10 simultaneous file-sharing connections

14.             
Security of disks and folders (NTFS drives)
limited Security, made difficult to use
Full Disk/Folder Security based on User Management
Group Policy Editor
not included
Included
Remote Desktop Access
not included.
                
Backup Program
only included via VALUEADD
ASR Automatic System Recovery