at least in the theory moreover,the 8088 differed from the z80 in two significant ways.it had wider internal registers and a greater memory addressing range.the 8088 was truly an 8-bit processor in that information moved in and out of the chip 8 bits at a time and while the z80 could only address 65,536 bytes of memory the 8088 could handle 16 times as much 1,048,576 bytes.potentially the 8088 was a more formidable microprocessor. Even in the early 80's more powerful chips were available ,how ever.for example: The bigger and older brother of 8088 the 8086 for in stance had the same 16 bit internal architecture the same wide addressing range and also used 16 bit connections with the out side world.the difference potentially made the 8086 twice was the fast 8088 even when operating at the same speed. IBM had one good reason for the foregoing the full 16 bit power of the 8086 however,in the early 80's the price of mircoprocessor support chips as well as memory was much higher than today using a full 16 bit bus structure would add substantially to the cost of the computer using it.Going with a 16 bit architecture probably did not make sense to IBM's pc Designers as the marketing move,particularly since the 16 bit internal nature of the 8088 would still allow IBM to advertise the erstwhile 8 bit pc as a 16 bit computer,however power was not a reall issue.Although the 8086 brain would have resulted in a superior machine,the market place placed no demands on performance,after all having a computer was vastly
better than not having one,and in comparison the performance difference between 16 and 8 bit designs was insignificant .and 8 bit design would be easier and faster to implement had no relative market disadvantage and was less costly (a powerfull advantage) The 8088 won out over the 8086.Other chips were out of the running.The motorola 6800,a full 16 bit chip,lost partly for the same reason as the full 16 bit 8086,and partly because it lacked easy CP/M translatability.The texas instruments family for microprocessors lost out for the same reason.as a result the 8088 was chosen,not quite an arbitary or capricious decision,but one that lacked the foresight to see performance arising as a major issue in microcomputers...
