Processor And Memory

• Microsoft recommends that your computer have a processor with a clock speed that is no less than one gigahertz. It can support 32- or 64-bit computing, though. The computer should also have at least 1 gigabyte of system RAM memory.
  
  

Drives

• For best performance, the Vista Business Update should only be installed on computers with a hard drive that is at least 40 gigabytes. It will need to have 15 gigabytes free for the installation process. In addition, because the Vista upgrade ships on a DVD, your computer will need to have an internal or external optical drive that can read DVDs.
  
  

Graphics

• To take full advantage of Vista Business' Windows Aero graphical interface, your computer will need a graphics card that has passed the Windows Driver Kit's Aero acceptance test. These cards typically support DirectX version nine or better, have a hardware based Pixel Shader and support 32 bit per pixel color depths. In addition, they will need to have a driver for the Windows Display Driver Model.
  
  

Miscellaneous Requirements

• Windows Vista Business requires a computer that can connect to the Internet. It is also designed to work on systems which have an audio output capability.
  
  

Existing Operating Systems

• Depending on what operating system your computer is running, you may be able to use the Windows Vista Business Upgrade to install the operating system without wiping out your current installation. Operating systems that allow for an "in place" installation include Windows XP Professional, Windows XP Home and Windows XP Tablet. If your computer is running Windows XP Media Center, Windows XP Professional 64-bit or Windows 2000, you will need to do a "clean install" of Vista Business, which will also require you to reinstall your software.