mainframes and other stuff

[Jon Elson]

On 11/21/2014 09:28 PM, William Donzelli wrote:
>> Actually, IBM gear had VERY little gold in them.
> Have you seen the inside of a 4381? There is a large array of
> multichip modules, sort of forerunners of the air cooled TCM - each
> one has almost 1000 gold plated pins.
>
>> So, a good-sized 360 mainframe had a couple Oz. of gold, total.
> The NASA model 67 reportedly had 66 ounces of gold in the CPU. Even an
> early model 30 could have 8 or 9.
>
> It is true that midway through the S/360 period and into the S/370
> period, the gold was really trimmed away to save costs - thus my wide
> range of values for 3803 tape controllers (they usually have a random
> mix of gold and tin backplanes).
>
> --
> Will
>
Well, still, compared to some other makes, IBM really cut 
down on gold use in their
machines.  The earlier SMS machines had a lot of gold in 
them, quite similar to
DEC Flip-Chip construction, in fact.

I guess my experience with the IBM gear must have been the 
later stuff, 360
models 50 and 65, and then I actually got to dismantle a 145.

Jon