Date: Wed, 30 Aug 1995 14:43:52 +0930 (CST) From: Michael Smith <msmith@atrad.adelaide.edu.au> To: rgrimes@gndrsh.aac.dev.com (Rodney W. Grimes) Cc: msmith@atrad.adelaide.edu.au, hardware@freebsd.org Subject: Re: S.O.S -2.1Stable and ASUSP54TP4 Message-ID: <199508300513.OAA27796@genesis.atrad.adelaide.edu.au> In-Reply-To: <199508300357.UAA05821@gndrsh.aac.dev.com> from "Rodney W. Grimes" at Aug 29, 95 08:57:00 pm
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Rodney W. Grimes stands accused of saying: > Yes, that is why you see all the mosture proofing. The problem is if the > plastic obsorbos mosture prior to soldering, that mosture boils and expands > quite rapidly when it hits the vapor phase, this causes micro cracks in the > plastic, that then allow mosture to easily pentrate the package and cause > ion contamination, which causes corrossion, which is very nasty/ugly for > the chip. Neat; means I can stop worrying about it, as we're small enough to do everything by hand 8) > Your back in the 80's again, bond wire stress does not exist in plastic > packages, the bond wires are either a) totally gone due to TAB bonding > between the die and the lead frame, or b) supported by the plastic used > in encapsolation (ie, there is _no_ die cavity to speak of any more). > That does not hold true of PGA or other cavity type packageing, but I > haven't seen any of that stuff on disk drives lately! I was actually thinking of CPUs at that point, and the extremely scungy fans that get mounted on them. (And the number of cases that seem to resonate with one or more of the spinning items inside) > By American Enhance power supplies, the are made in Taiwan, but they use > a ball bearing fan, and American Enhance long ago learned all about fan > failures and how to fix them :-). Remeber, those low dollar clone manufactures > are targeting the home PC market, where the MTPO (Mean Time Powered On) is > only about 3 weeks a year :-). Hah! Buy a Name Brand in australia? You gotta be kidding 8( Seriously, I've considered the relative possibilities in running a version of AA on my spare time here, but a) sourcing good parts is close to impossible, and b) the only 'right price' around here for PC parts is the lowest one 8( > Rod Grimes rgrimes@gndrsh.aac.dev.com -- ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[ ]] Genesis Software genesis@atrad.adelaide.edu.au [[ ]] High-speed data acquisition and [[ ]] realtime instrument control (ph/fax) +61-8-267-3039 [[ ]] My car has "demand start" -Terry Lambert UNIX: live FreeBSD or die! [[
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