Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!apple!julius.cs.uiuc.edu!zaphod.mps.ohio-state.edu!maverick.ksu.ksu.edu!unmvax!ariel.unm.edu!nmsu!opus!ghenniga From: ghenniga@nmsu.edu (Gary Hennigan) Newsgroups: comp.sys.ibm.ps2.hardware Subject: 8088 and 8086 was: Message-ID: Date: 3 Nov 90 06:22:43 GMT References: <1990Nov1.120159.20396@ioe.lon.ac.uk> Sender: news@NMSU.Edu Organization: NMSU Computer Science Lines: 43 In-reply-to: teexmmo@ioe.lon.ac.uk's message of 1 Nov 90 12:01:59 GMT In an article teexmmo@ioe.lon.ac.uk writes: (Esa Holmberg) writes: >> >> Once more.. PS/2 model 30 has 8086, not 8088, and >> model 30-H has 80286.. > >Perhaps the reason that people make this dreadful mistake is that they >dont know what the difference between an Intel 8088 and 8086 is. > >If its not too much trouble, could you tell us what the differenc eis, >and why its important? Matthew, There's really only one major difference between an 8088 and an 8086 and that's the bus size. Just in case, a bus is the way a CPU gets it's info from the outside world, eg., memory, ports and other assorted hardware. The 8086 was the first CPU that could be categorized as a "PC" type, at least in Intel and IBM terms. It's architecture was 16 bit internal and a 16 bit bus. Sounds like a good match, but, when it was first introduced the price was outrageous even by today's standards, so IBM, and Intel, decided to make a cheaper PC by limiting the CPU's access to the outside world to be only 8 bits while keeping the "power" of the sixteen bit internal architecture. While at today's rapidly decreasing prices that doesn't make much of a difference, at the time it allowed IBM to significantly reduce their prices which is what was needed to really "settle" the PC into the lives of consumers. Must have worked! Today I don't think many more 8088's are sold, since that mismatch in bus and CPU can be a major bottleneck and the price/performance is reasonable any more, but fear not the mismatch is still present in the form of the 386sx (32 bit internal 16 bit bus)! Well that's kind of a long explanation but I hope it helps. -- Gary Hennigan +---------------------------------------------------------------------------+ + e-mail: ghenniga@NMSU.Edu, henninsf@maxwel.NMSU.Edu + + Department of Electrical Engineering, Grad Student + + Physical Science Laboratory (ASS)istant systems programmer + +---------------------------------------------------------------------------+