On Tue, 12 Sep 2000, Carlini, Antonio wrote:

> 	Remind me to tell you about the day I thought I'd destroyed a
> 	VAX 6000-400 ... In fact I've been told by a former FS engineer
> 	that he could often fix faults with BI boxes by just reseating the
> 	boards. So now we know it's true for XMI and Qbus too
> 	(although given the levers used to push those boards in
> 	I'm somewhat surprised).

This tendancy is usually found in vme busses and others as well I suspect.
A machine (vaxen, old suns etc) will happily run for years on end without
problems, but if it is allowed to cool down (especially for a longer
period) I usually haft to reseat all the boards. If that doesn't help
sometimes a hard glass-fiber brush to the edge connectors makes the system
happy again.

I suspect thermal contraction makes the board move slightly so the
connection point moves up onto an oxidized/greasy layer on the
connector. You shouldn't give up easily on these old systems, they are
built to last. :-)

Peter
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