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eisa

An acronym for Enhanced Industry Standard Architecture. A well thought out computer expansion bus used in high end 386 and 486 PC's and some Techtronix and Hewlett-Packard Workstations. A non-proprietary industry-wide attempt to counter IBM's MicroChannel bus. (This lasted 7 years; when was the last time you saw a MicroChannel computer?) A bus width of 64 bits allowed a 33mbs transfer rate (fully 32 bit operational), making it ideal for file server computers with high disk I/O rates. Unfortunately the 8.25MHz bus speed made for high latency in small transfers, leading to poor video performance compared to the 32 bit, 33mhz VESA Local bus. To any extent, it was an effort by the industry to further technology and it worked beyond the original designers' wildest expectations. The PCI bus offered greater performance and capability. Initially PCI architecture was offered in conjunction with ISA boards. Now most systems are eliminating the ISA capability to gain additional performance. Those that still enable ISA are termed Legacy capable.

eisa.txt · Last modified: 2006/10/15 09:35 (external edit)