All that glitters: gold SIMMs lose their shine
(installing memory chips)(Second Looks) (Technology Tutorial)(Brief Article)

Author
Machrone, Bill

Full Text
Readers have begun to report an insidious problem with their in-line memory
modules: corrosion caused by incompatibilit ies between the gold plating on the
SIMMs and the sockets on the motherboard.

Within the past two years, most manufacturers have switched from gold-plated
sockets to tinned sockets, in the quest fo r ever-lower prices. The tinned
sockets require matching SIMMs with tinned edges. Installing SIMMs with gold
contacts i nto tinned sockets causes no immediately apparent problems but sets
the stage for corrosion that will eventually destro y the socket.

This is no small problem: A dead memory socket is as good as a dead motherboard.
Installing newer, tin-plated SIMMs int o an older machine with gold-plated
sockets is also a recipe for disaster. High-humidity conditions make the
corrosion worse.

If you're planning to add more memory, check your sockets (and your existing
SIMMs) before ordering more chips. The gol d plating is easily visible as thin
gold lines in the bottom of the socket or as gold fingers on the bottom of
SIMMs; t inned sockets have silvery gray lines. If you find that you have gold
SIMMs factory-installed in tinned sockets, call y our factory service rep and
hope for the best.

In all likelihood, relatively few machines were built this way, but if you've
got one, it's an accident waiting to happ en. If you've installed the wrong
SIMMs yourself, you've probably voided your warranty. (Remember to ground
yourself to
 the machine before adding or removing memory to prevent damage to the PC or
injury to yourself from static electricity .)


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All that glitters: gold SIMMs lose their shine
PC Magazine: Dec 5, 1995
COPYRIGHT Ziff-Davis Publishing Company 1995
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