MIKE ROSS wrote in a message to Thurston Ackerman:

 TW> Actualy for hte medical equipment they recomended leaving the
 TW> Contacts Dry.

 MR> Many contact cleaners tend to leave a residue which improves the
 MR> conductivity of the metal contact but I've found in some high
 MR> impedance circuits that this residue causes current leakages. Not
 MR> so good for fet inputs for example and I always cleaned these off
 MR> with 99% iso... 

This is a *real* important point,  when it comes to contact cleaners. 
There are basically two kinds out there,  those that leave a residue
("lubricating", etc.) and those that don't.  I've always tended
to favor those that don't.

 TW> The Chips had a tendenacy to work their way out of the sockets 
 TW> anyhow with the Heatup/CoolDown cycles. In fact Reseating All 
 TW> chips was part of the Quarterly PM routine.

 MR> I noticed some brands of sockets were better with chip creep than 
 MR> others. Many early cheap XT clones for example always needed the 
 MR> dram pushed down every few months as their chips kept climbing out
 MR> of their sockets relentlessly.

I'd guess that depends on the design of the contact _and_ on what metals
were being used,  both in the chip legs and in the socket material...

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