By Andy Dwelly, Developer, Condign Systems, UK
So I built a dogecoin mining rig ' as you do.
Well, perhaps it was not quite as straightforward as that. I'd become aware of Dogecoin a few weeks into the new year, and thought: "fun _and_ profit, what could possibly go wrong?' Well, I did get a few things wrong, and it would be a stretch to call the whole experiment profitable so far ' but it has been fun.
Dogecoin, if you hadn't heard of it, is one of a growing family of crypto currencies that are alternatives to Bitcoin. Each one offers a supposed advantage: Darkcoin is hardened to improve anonymity; Litecoin is more suitable than Bitcoin for mining with cheap GPUs; and Dogecoin, er, offers a picture of a silly internet meme ' a Japanese Shibu Inu dog in fact (1).
Despite its seeming lack of features, when Dogecoin was introduced in 2013, it became wildly popular. Some users managed to pay for the Jamaican bobsled team to go to the Sochi Winter Olympics; others funded a project involving puppies working with the visually handicapped. The whole Shibu thing looked like a very savvy marketing move, and although I find it slightly odd to mention 'currency' and 'marketing' in the same sentence, it did seem to be working. I did a bit of research, priced out a rig that would pay for itself within 18 months, and then decided ' generously ' to offer the "chance of a lifetime' to my co-workers.
I did this:
- So they wouldn't ask why I was spending so much time staring at Reddit crypto currency subreddits, and
- So I could take advantage of the office's free electricity.
(The electricity is not really free of course, but it doesn't cost the company where I work either ' it's part of the lease agreement. We checked the lease contract and strangely enough there is no mention of crypto currency mining in the 'forbidden activities clause', although I was surprised to discover that we'd promised not to run a house of ill repute. I mean ' really? Had the building manager seen us? We're hardly HoIR material.)
Deciding what parts to order turned out to be surprisingly easy ' there's plenty of information out there on which motherboards, GPUs, cabling systems, and so on, could be assembled to make a GPU-based mining rig. As it happened, the only sticking point was that I'd forgotten to include an on-off switch, and nobody seemed to want to talk about power supplies. In the end we used a paperclip for the switch and the cheapest power supplies we could find. They cost about £40 (CDN $73) and I think were made by a division of the Chinese Red Army that normally handles tractors. We didn't bother with a case: a desk draw with some duct tape and recycled cardboard folders did the job.
You can see the 'Frankenrig' running here, and astonishingly, it did actually mine Dogecoin.
Soon after I got it running, I departed on a long delayed skiing holiday in Norway in a happy (and entirely delusional) state of mind.
I was several miles along a ski track with only my family and a passing polar bear for company when I got a call on my mobile:
My co-workers: We've decided to add some more cards, can we use your Amazon account to get another power supply?
Me: No problem, but I really think we need to get a better brand of supply ' how about Corsair?
My co-workers: Nah ' these are working fine.
Me: Um, actually'¦
My co-workers: <click>
The bear rolled its eyes at me and went off to investigate a nearby seal hole.
When I got back to the office, the rig was running with one extra card and another 'Red Army' brand power supply in parallel with the two others. The whole thing operated for about three hours and then unceremoniously shut down ' one of the supplies had given up the ghost. We sent it back but rather than wait for a replacement, I schlepped out to the local computer shop for a similar supply. This one lasted a few minutes before shutting down, and also bringing down the breakers to our office.
Most of our office building is occupied by a video games company. We often see its employees wandering around the corridors with bored or haunted expressions on their faces: they know that, like the soldiers of WW1, they will soon be ordered over the top to face down a storm of oncoming C++ bugs (each object pointing to another one and saying 'that's me over there'). Personally, I feel sorry for them (I mostly program in a variety of Lisp these days, (it turns out Paul Graham was right (who knew?))).
We borrowed one of their very high end power supplies: a work of art with a solid feel to it and the cables separately packaged in an ivory inlaid mahogany box (2). Plugging this one in melted the wall socket and took out the entire floor. Fortunately, my assumption was that we'd managed to run 35 amps through a motherboard and 4 GPUs turned out to be incorrect when we had the wiring checked ' by some miracle the valuable bits had survived.
So we put together a new frame, bought a new proper power supply and put together the rig you see here.
It's worked perfectly (and more or less uninterruptedly) since.
Alas, while this was all going on, the value of Dogecoin dwindled away to around a tenth of what it was when we started. Last week, we regretfully decided to give up on Dogecoin. The rig is currently beginning to work on Litecoin. I've got almost a hundredth of one of those now!
(1) Checking last week I discovered that there's now Gaycoin. Don't ask.
(2) This is an exaggeration, it was polyester and velcro'¦