group buy for homebrew CPUs?

[William Donzelli]

 >    Very true...but I've looked far & wide for a reason for that
> specification to exist, and have found none.  The only thing I can
> think of is the possible flattening out of the balls causing them to
> short against adjacent ones...but is that really possible?  Not sure.

I suspect the spec may be due to what IBM found with SLT developement
in 1963 (which was basically BGA on a small scale) - having some
height allowed for a small moment arm, which was good for absorbing
the flexes due to thermal expansion as the chip heats up.

--
Will