[rescue] Design question.

[joshua d boyd]

OK, this isn't really rescue related (unless people here spend 6 figures
to rescue brand new computers), but some peope subscribe here that
might have usefull things to say, but they don't subscribe to geeks.

Anyway, I was reading some John Mashey notes on the O*3k machines from
SGI (at http://www.cwi.nl/~robertl/mash/numaflex).  In commenting about
PCI bricks, he says:

	All I & P-brick PCI cards are (in hardware) warm-plug, with horizontal
	insertion/removal from the rear, using a plastic carrier that
	pushes the PCI card down as needed.
	
	[Big-system hardware designers are not fond of PCI's insertion at
	right angles to the external connectors. Note, for example, that
	Compaq's GS320 documentation says nothing about warm-plug PCI.

So, what is the problem with PCI cards, and why is it a problem?  Is he
implying that SBus is a better physical design for heavy metal?

Also, to the physical description in the first paragraph.  Is he
describing something that would be like a drive tray, but it holds a PCI
card instead of a drive?  Has anyone seen what these things actually look
like?

BTW, he makes it sound like IR3 is just IR2 hacked into the new
environments.  I guess what I'm hearing about IR3 performance numbers
backs this up.

-- 
Joshua D. Boyd
http://www.cs.millersville.edu/~jdboyd/