Contact fingers is one of the things I worked on at HP. Like why do they not
make contact. Sorry about the carbon, not so. It happens mostly because
there is very little gold on the contacts. Gold is expensive. You have to
plate enough of it to close most of the holes in the plating, but that takes
a lot of gold, so they just barely plate enough to close most of them.
Closing all of them is almost impossible anyway.
What happens is moisture in the air helps make a small battery out of the
different metals and it produces by products that are like crystals that
actually form an eruption at a hole site. As it erupts from corrosion, it
lefts the fingers. This is similar to what happens when you see rust. Rust
is the eruption stuff. But it's iron so it looks brown. The contact salts
are green to blue, mostly, if you can see them. You need a good microscope
to see most of them. Now when the crystalline salts are wet, they are
conductive, but when they dry, they are insulators, so bad connection.
This is one of the reasons your computer might not work at home, but when
you put it in your car and take it down a bumpy road to the shop, it
vibrates and may clear. When you get to the shop, it all works fine, until
you take it home and the process continues and eventually, the same problem,
again.
We determined that an eraser should not be used as it just also removes more
gold so you can make the problem even worse in time.
The right way to clean them is with a combination of about seventy five
percent alcohol to twenty five percent clean water. A lint free cloth is
used. Just water or just alcohol will work ok too.
This is also why you will see grease like substance on phone contacts and
other contacts. Grease will work fine for this, as long as contacts don't
open and close like in a relay. If they open and close, the grease stuff
will burn when it makes or breaks contact and then, Sandi, the carbon stuff
will form. The grease stuff forms a barrier to moisture and air, two things
you also need to cause corrosion. Oil in the grease is what forms the
barrier. So, one could also use a small bit of oil also.
More then you wanted to know. :O)
Bob Noble
www.sonic.net/bnoble
----- Original Message -----
From: "Huntress" <sanneumann@xxxxxxxxxxx>
To: <pcductape@xxxxxxxxxxxxx>
Sent: Sunday, December 19, 2004 7:59 AM
Subject: [pcductape] Re: STOP error (moved to Freelists)
He's saying that he has had this happen on a few Dells recently and the
problem was with the RAM contacts becoming dirty so you have to take them
out and clean them with a pencil eraser and put them back in. The "dirt"
is actually carbon deposits that can be caused by voltage fluctuations. :-)
Sandi
----- Original Message -----
From: trapper
To: pcductape@xxxxxxxxxxxxx
Sent: Saturday, December 18, 2004 11:41 PM
Subject: [pcductape] Re: STOP error (moved to Freelists)
Are you saying that a re-seating of his memory is all that is needed??
Hi De,
I cannot boot to bios. I cannot boot to A drive. I cannot boot to my CD drive. I cannot boot to my DVD drive.
Carl
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