#IDE – SCSI
The problem with this fragmentation (and I agree with you on that) is that it
gets harder for hardware manufacturers to select a bus to support. It ain't
cheap designing boards for ISA, EISA, VLB, and PCI all at the same time. It's
even more expensive to design mother boards. The manufacturers are going to
have to "select" one and see hoppe for the best. The bus who gets the greatest
number of manufacturers wins. EISA bus is mostly being used for network servers
as both SCSI and NIC support is strong in EISA. Machines designed around EISA
today are thought out as straight file servers. You won't find a EISA "desktop"
machine that easily. ISA is the common denominator. All of the above support
it. VLB got a lot of attention in the past year. Just about every video board
out there has a VLB version (just a very few EISA and that's for the reason
stated above, EISA = file server). PCI started sorta screwed up but gained a
lot of momentum and seems to be the "hot" thing on the market today (it doesn't
mean it will last longer than tomorrow as this market is more volatile than
processed chili beans)…
I guess we all agree with this in one way or another. The point I was trying to
make was that EISA was the "obvious" choice two years ago as it could not be
any other way. It's just that it took them too long to have the product out and
they may now be facing a situation where they are already late and to consider
a bus change would make it even later.
Technically speaking, ISA is limited to 8Mhz and 16 bit transfer. EISA is
limited to 16MHz and 32 bit transfer. Both VLB and PCI are limited to 33MHz and
32 bit transfer. That in itself shows the route of things. Note that to break
that, they will have to "invent" something. Increasing the buss width will make
the connector too long (say, a 64 bit bus). Increasing the bandwidth will make
it almost impossible to avoid leaks (connector to connector signal leak) and
interference (you will be able to "tune" your computer on channel 2).