User:BF10/Sandbox/5

System requirements
According to Microsoft, the following are the recommended system requirements for Windows 1.0 and its beta releases. This table takes account retail versions; OEM versions will vary depending on the hardware that it was intended to be installed on.

Compatibility
Windows 1.0 does not officially support MS-DOS versions above MS-DOS 3.x due to a bug in the logo code that does not accept MS-DOS versions outside of MS-DOS 2.x and 3.x. All versions of Windows 1.0 will crash on startup on MS-DOS 4.00 and above if  is not run on   to report a MS-DOS version between 2.00 and 3.31.

System requirements
According to Microsoft, the following are the recommended system requirements for Windows 2.x, including Windows/286 and Windows/386 releases. Windows 2.1 drops support for installing on two floppy disks and requires a hard drive to install Windows on.

This table takes account retail versions; OEM versions will vary depending on the hardware that it was intended to be installed on.

Compatibility
Windows 2.x does not officially support MS-DOS versions above MS-DOS 3.x due to a bug in the logo code that does not accept MS-DOS versions outside of MS-DOS 2.x and 3.x. All versions of Windows 2.x will crash on startup on MS-DOS 4.00 and above if  is not run on   to report a MS-DOS version between 2.00 and 3.31.

Additionally, 386 enhanced mode for Windows/386 will not boot on MS-DOS 5.x and above due to a conflict with HIMEM included in these MS-DOS versions. Windows will immediately exit if  is entered in these MS-DOS versions, and can only be booted via   in this case. Likewise,  cannot be loaded in a window if Windows is installed on MS-DOS 5.00 or above.

System requirements
According to Microsoft, Windows 95 requires an 80386 processor, at least 4 MB of RAM, 50-55 MB of hard drive space (varies depending on components being installed), and an EGA, VGA, or better display adapter. Windows 95 drops support for the 80286 standard mode and the Hercules and CGA display adapters. Windows 95 allows installation to be possible without a floppy drive via CD-ROM media, although a floppy drive is required if one wants to make a startup disk.

Hardware compatibility
Windows 95 does not support AMD processors faster than 350 MHz and Intel processors faster than 2.1 GHz due to a divide-by-zero via bugs of timer calibration in several drivers. Additionally, Windows 95 does not support having more than 480 MB of RAM due to a bug in the memory allocator. Windows 95 will often encounter system instability or crashing upon boot on these systems without additional fixes.

System requirements
According to Microsoft, Windows 98 requires a 486DX 66 MHz processor, at least 16 MB of RAM, 175 MB of hard drive space (varies depending on components being installed), and a VGA or better display adapter. Windows 98 drops support for EGA display adapter. Windows 98 Second Edition drops support for floppy installation and requires a CD-ROM drive to install.

It is possible to bypass most of these requirements via the  parameter for. By doing so, it becomes possible to install Windows 98 on an 80386 processor with as low as 4 MB of RAM.

Hardware compatibility
The original release of Windows 98 does not support AMD processors faster than 350 MHz and Intel processors faster than 2.1 GHz due to a divide-by-zero via bugs of timer calibration in several drivers. Additionally, Windows 98 (both the original release and Second Edition) does not support having more than 1 GB of RAM due to a bug in the memory allocator. Windows 98 will often encounter system instability or crashing upon boot on these systems without additional fixes.

System requirements
According to Microsoft, Windows Me requires a Pentium 150 MHz processor, at least 32 MB of RAM, 320 MB of hard drive space (varies depending on components being installed), and a VGA or better display adapter.

It is possible to bypass most of these requirements via the  parameter for. By doing so, it becomes possible to install Windows Me on a 486 processor with as low as 8 MB of RAM. Windows Me drops support for the 80386 processor.

Hardware compatibility
Windows Me does not support having more than 1 GB of RAM due to a bug in the memory allocator. Windows Me will often encounter system instability or crashing upon boot on these systems without additional fixes.

System requirements
According to Microsoft, Windows XP requires a Pentium processor, at least 64 MB of RAM, 1.5 GB of hard drive space, and a VGA or better display adapter. Windows XP drops full support for processors without the CPUID instruction, like the 486. Additionally, the HAL for the SGI Visual Workstation 320 and 540 is no longer included in Windows XP. Windows XP updates the default VGA driver to take advantage of VESA BIOS extensions, allowing true color display and resolutions in the default VGA driver, although this requires a graphics card that supports SVGA.

System requirements
During development of pre-reset Longhorn, the system requirements were largely the same as Windows XP, with the sole exception of build 4001, which requires a Pentium III processor or better. However, most builds of Longhorn only installs on NTFS partitions, which would be carried to the final release of Vista. Throughout development of post-reset Vista, the system requirements were significantly increased to accommodate new computing standards, such as the use of WDDM to take most advantage of display capabilities.

According to Microsoft, Windows Vista requires a processor with a speed of at least 800MHz, at least 384 MB of RAM, 15 GB of hard drive space, a SVGA or better display adapter, and DVD-ROM drive. Windows Vista drops support for systems without ACPI. CD-ROM installation is still possible, but such installation method now uses multiple CD-ROMs due to the increased size of the installation media after the shift to WIM installation, and wasn't offered in retail.

Windows Vista's setup doesn't check for a required processor generation or speed to install so long as setup can start, and thus it is possible to install Windows Vista on processors as early as the original Pentium.

Hardware compatibility
Intel CPUs whose microarchitectures are based on Haswell or later are not supported on Windows Vista. Numerous issues relating to certain services or applications failing to start on the affected CPUs have been reported by various users, with extreme cases often leading to potential bugchecks. The KB4493471 update contains a new version of the HAL (hardware abstraction layer) that fixes most of these issues.

Windows XP, earlier operating systems and x86 versions of Windows Vista are not affected by the aforementioned problems.