Bitcoining on a 1401

Marc Verdiell marc.verdiell at
Fri May 29 16:18:14 CDT 2015

We do have two 1401s, and on a good day, they both work. No working 360s. But even if we could have the two 1401's talk to each other, it would still take about the age of the universe to mine a block. This is about the worst machine for scientific calculation, as it does BCD, character by character arithmetic, in a serial fashion, one BCD digit at a time. Hardware multiplication is an optional add-on feature on these machines (which we have)!

So no, you can never mine a real block in time with a 1401, or even a million of them. But that you could implement and run the algorithm is just a testament that the fundamentals of computing haven't changed, doubled with a vivid demonstration of the mind-boggling effects of Moore's Law over one generation. And having old hardware tackle modern tasks is just plain fun. And, lest I forget, a credit to the skill, talent and humor of our vintage programmer extraordinaire Ken, who joined us recently.


Message: 13
Date: Thu, 28 May 2015 12:31:57 -0700
From: Brent Hilpert <hilpert at>
To: "General Discussion: On-Topic and Off-Topic Posts"
   <cctalk at>
Subject: Re: Bitcoining on a 1401
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On 2015-May-28, at 11:12 AM, Fred Cisin wrote:
>>> Is the bitcoin output anywhere close to enough to pay for the costs of
>>> running a 1401?
>> On Thu, 28 May 2015, emanuel stiebler wrote:
>> Probably not. Quoting the web page:
>> " ... but so slowly it would take more than the lifetime of the universe to successfully mine a block "
>> ;-)
> Excellent!
> Does anybody have enough 1401s to run them in parallel to speed up the process?

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