Oops, I am a bit too tired, and something was bugging me about your calculations. PPros have more than a third of a gram - they are closer to a gram per unit. -- Will On Tue, Nov 25, 2014 at 1:08 AM, William Donzelli <wdonzelli at gmail.com> wrote: >> Let's say that a Pentium Pro has a third of a gram; a troy ounce is >> 31.1 grams; so 94 Pentium Pro to the troy ounce; 4.5 pounds is about >> 65 troy ounces; so 6,182 Pentium Pro might have that much gold. > There are 12 troy ounces to the pound, not 16. > > Anyway, yes, you are talking about something like 4800 PPros > equivalent. Now compare the plated surface areas of a PPro compared to > a number of the pins on the backplane - you will find that a gold > plate area on a PPro (mind you, there is a fair amount under the > cover, too) equates to a surprisingly small amount of old IBM > backplane pins. Remember, the pins are long, and plated on four sides > - and probably had a thicker plate that on PPros. > > And yes, the 75 was a really huge machine. Gold on the backplanes, > gold on the connectors (early Bus&Tags have a very heavy plate), gold > in transistors. I would not be surprised if there was gold in the lamp > sockets. > > -- > Will

Well, that is very interesting. Based on other sources, the numbers are all over the place, however. I will ask some people directly what they know.