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Re: Todays Nasty little problem: Defeat the BIOS



On Friday 30 September 2011 19:39:46 owens@netptc.net wrote:
> ----- Original Message -----
> From: Harry Putnam
> To: debian-user@lists.debian.org
> Sent: 9/30/2011 9:29:48 PM
> Subject: Re: Todays Nasty little problem: Defeat the BIOS
> 
> Terence <terence.john@gmail.com> writes:
> > On 30 September 2011 21:27, Harry Putnam <reader@newsguy.com> wrote:
> >> Just reporting back.  After pulling the card blowing everything out
> >> and reinstalling the card, I got video back.  Not only that but a DVI
> >> outlet on that card that hasn't worked for a good while, began working
> >> too.
> > 
> > Can you give us more details?
[snip]
> 
> I pulled out the video card, (an MSI nvidia FX 5700LE) took a can of
> compressed air, and blew around the card seat. I went ahead and
> blew out all around the cpu, rear fan, power supply vents and fan and
> all other components I could get too.
[snip]
> I think now, that dust was not the problem... I suspect the card had
> become dislodged to some small degree. That machine has been moved a
> good bit recently. So I really think reseating the card was what
> really did the work.... I'll never know for sure.
> 
> Often when the card has been removed it is useful to run a pencil eraser
> over the pins to clean them.
> 
> Larry

Gold contacts are not pure gold, they consist only of a more or less fine 
layer of gold on copper. The copper atoms migrate through the gold and react 
with the oxigen of the air and become an insulator. This is known for many 
decades. Indeed a white, soft eraser takes the copper oxide off. Never use a 
red one which contains abrasives.
CPUs not working after pulling the boards for maintenance were a well known 
problem of the WANG 2200 CPUs. Every technician was afraid to pull the boards. 
Better don't touch a running system. Of course with wobbly computer cases and 
relatively huge motherboards and PCI-cards screwed to the rear panel a slight 
movement can produce the same effect. Getting rid of the copper oxide can 
solve the problem. Only the contacts of the slot connectors are inaccessable. 
Moving the board in the slot connector also scratches the copper oxide off the 
contacts, which ought to be designed self-cleaning. Self-cleaning does not 
work however if the male connector is never pulled out and reinstalled. That 
also is well known. Canon connectors for audio e.g. are constructed in a way 
that they self clean when plugged in and out. Having connectors not moved for 
many years cause all kinds of nasty static.
Telephone connectors, on the other hand, are made gas-tight, which means that 
oxigen cannot get between the two contacts. That is because in telephone 
systems the connections are rarely disconnected and connected again. They may 
indeed stay untouched for many decades.

But there is another problem with old (>4-5 years, depending on the heat) 
electronics which run relatively hot: dried out electrolytic capacitors. This 
problem cannot be solved by reseating the card, of course.

Glad that you could solve the problem.

Eike


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