A Brief History of Computing

© Copyright 1996-2001, Stephen White

Last update: 28/3/2001

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Intel 486

80486SX-25
Photo by author
Intel 80486SX-25 Processor

The 80486 processor was released by Intel on April 10th 1989. It contains the equivalent of about 1.2 million transistors. At the time of release the fastest version ran at 25MHz and achieved up to 20MIPs.

Later versions, such as the DX/2 and DX/4 versions achieved internal clock rates of up to 100 MHz.

The 80486 SX (pictured here) was released on April 22 1991, as a cheaper alternative to 80486 DX - the key difference being the lack of an integrated F.P.U. (floating point unit).

The author's family used this opportunity to replace their Amstrad PC 1512 with a new machine in August 1991. It cost 1210.26 and had a 20 MHz 486sx, 4 Mb of RAM. a 212 Mb IDE hard disk, and a 1 Mb SVGA card. It ran MS-DOS 5.00 and Windows 3.1 (at up to 1024x768x256 colours). It was soon upgraded to 8 MB of RAM and 500 MB hard disk, then a Sound Card and triple speed CD-ROM were added.




© Copyright 1996-2001, Stephen White My homepage - email:swhite@ox.compsoc.net