FDDI, was: Re: [rescue] u2 drive trays

Eric Dittman dittman at dittman.net
Wed Aug 20 12:03:10 CDT 2003

> >>    Yeah that'd be neat...I just wish Qbus weren't so blasted SLOW.
> >>
> >>    Qbus was a introduced as a smaller, lower-cost alternative to 
> >> Unibus,
> >> which runs at TWICE the speed of Qbus.  (Qbus multiplexes the address
> >> and data lines on the same backplane wires) If they really had to
> >> discontinue one and keep the other, they should have kept Unibus!
> >>
> >>    So much for "newer" automatically being "better".
> >
> > XMI?
> > VAXBI?
>    But those *are* better.

Yes, and they should have discontinued both UNIBUS and QBUS in favor of
them both, but they were still doing QBUS until the end of the VAX
development.  I would have loved to have a BA440-sized cabinet that used
a 4000/700-speed CPU with a VAXBI or XMI bus instead of the QBUS.
Eric Dittman
dittman at dittman.net

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