Silicon makes up much more of the cost of a computer than copper, its not even close. Silicon is >50 cents a gram, copper is less than a cent per gram.
That's what the significantly was all about. We're not really going to run out of silicon any time soon, but we actually might with copper.
At the moment, both those prices are strongly dominated by the cost of processing, I would imagine. At some point, it could well be the scarcity you're paying for with copper, though.
Scarcity increases price, and two orders of magnitude is hardly inconceivable.
