Mystery IBM processor

Mike Ross tmfdmike at
Sat May 28 05:29:19 CDT 2016

On May 28, 2016 9:51 PM, <malcolm at> wrote:
> Just wondering if anyone can help us to identify a rather large IBM
> processor assembly. It weighs around 60 pounds.
> The frame has a P/N of 34F5089. The frame houses 9 modules, 6 of which are
> installed. The module we removed for inspection has a P/N of 34F0615.

Definitely IBM mainframe. The individual square alloy lumps are what are
called MCMs - Multi Chip Modules. Insides are dozens of individual ECL ICs.
Water cooling heatsinks would have been bolted to the front side in life.
Can't remember what IBM called the entire assembly. 1980s, probably a 3080
or 3090 but don't quote me on that.


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