|MadSci Network: Computer Science|
Hello, Leila. Your first question was: "what is the difference between microprocessor in buses and speed". Both the speed of the microprocessor and the speed of a bus (there are often several different buses in a computer system) are defined in terms of clock rates, which are in Megahertz (millions of pulses used as clocked signals per second). Here is a site that gives an overview of how the microprocessor works: The microprocessor has a speed or clock rate that is generally higher than the bus speed or clock rate. Here is an explanation why the microprocessor speed is different from the bus speed, from this website: http://www.comptechdoc.org/hardware/pc/begin/hwmotherboard.html "As PC technology grew, eventually the access speed of the memory could no longer keep pace with the increased speed of the microprocessors. At this point, an I/O [input/output] cache was placed on the microprocessor to be a buffer between the external memory on the motherboard and the internal processor registers. The memory was set to run at a different "side bus" speed which is some fraction of the microprocessor speed. Therefore when the speed of the microprocessor is set, it is set to some multiple of the side bus speed. In the case of a 500Mhz processor and 100Mhz PC100 capable memory, that multiple is 5. " -------------- You also asked: "how are speed or buses in 8088 (cpu)and how are in the others." The 8088 computer came out in 1979, and had a clock speed of about 5 MHz . This webpage has a historical perspective and a table with the clock rates of microprocessors over time: http://electronics.howstuffworks.com/microprocessor1.htm Here is a more recent article discussing microprocessor and bus speeds for more modern systems: http://www.technewsworld.com/perl/story/31594.html
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