Re: memtest86, built into kernel
Matti E Aarnio (mea@mea.cc.utu.fi)
Tue, 23 Apr 1996 10:17:41 +0300 (EET DST)
...
> >Even good RAM has some single-bit errors after a few weeks. It can be
> >caused by radioactivity (alpha particles) for example.
> Hmmm, where is your alpha particle producer in a closed computer box?
> When I remember my physics examination right, alpha particles are stopped
> even by paper, beta and especially gamma radiation are the ``difficult to
> limit'' ones. So I assume that the plastic cover on the RAM chips is
> protection enough, right?
Right for external alpha sources. These SEU alphas come from radio-
active impurities/isotopes at the silicon, aluminium, gold, casing
epoxy, ... (mostly the epoxy)
The impurity content is very limited these days -- chemical purity
is pretty good, but isotopic purification in mass quantities is not
commercially viable -- see Uranium 235/238 separation facilities as
an example of such system..
> Andreas
/Matti Aarnio <mea@utu.fi>