Heat Failures

[Rik Bos]

When systems get older they can get more sensitive to heat due to a process
called electromigration.
http://en.wikipedia.org/wiki/Electromigration 
When systems are a long time in use there is some displacement of chip
material witch is affecting the fysical characteristics of the chip, paths
are getting thinner and displaced material could cause shortcuts etc..
Another cause, could be bad connection or cold solder connections (overtime
solder crystalizes and becomes a semi-conducter).
Most times replacing the (over)stressed or heat sensitive parts by NOS-parts
do the job, and prolongs the lifecycle of vintage equipment.

-Rik

> -----Oorspronkelijk bericht-----
> Van: cctalk-bounces at classiccmp.org 
> [mailto:cctalk-bounces at classiccmp.org] Namens O. Sharp
> Verzonden: donderdag 26 februari 2009 21:19
> Aan: cctech at classiccmp.org
> Onderwerp: Heat Failures
> 
> 
> Hey, all:
> 
> I'm hoping for some info about older micros and heat failure. 
> We have an archaic system at work which is going stupid on 
> us, and we're looking at repair-or-replace options.
> 
> Let's say you have a system which is locking up due to heat 
> problems. I suspect we've all seen that from time to time. 
> We're talking failures where you can cool things down and 
> reboot and the system comes back and works again, not 
> failures where things are visibly melting and/or burning.  :)
> 
> Is there a "typical" mechanism by which heat causes a system 
> to go south?
> 
> If you get a system which is knocked out by heat, does it 
> make it more prone to being knocked out by heat in the 
> future? In other words, do heat failures make a system 
> physically more susceptible to more such failures - is the 
> damage cumulative?
> 
> Any relevant info appreciated. Thanks!
> 
>                   -O.-
>