Windows XP removed support for PC-98, i486 and SGI Visual Workstation 320 and 540 and will only run on 32-bit x86 CPUs and devices that use BIOS firmware. As a result, Windows XP is the first consumer edition of Windows not based on the Windows 95 kernel or MS-DOS. However, in January 2000, both projects were scrapped in favor of a single OS codenamed 'Whistler', which would serve as a single platform for both consumer and business markets.

An updated version of Windows 2000 was also initially planned for the business market. It is a direct upgrade to its predecessors, Windows 2000 for high-end and business users and Windows Me for home users, and is available for any devices running Windows NT 4.0, Windows 98, Windows 2000, or Windows Me that meet the new Windows XP system requirements.ĭevelopment of Windows XP began in the late 1990s under the codename ' Neptune', built on the Windows NT kernel and explicitly intended for mainstream consumer use. It was released to manufacturing on August 24, 2001, and later to retail on October 25, 2001. Windows XP is a major release of Microsoft's Windows NT operating system.

Windows xp service pack 4