On Bitcoin Mining 8

Here we go, just another chapter in a Bitcoin mining adventure.

So, I had a perfectly good Bitmain Antminer R4 earlier this year and when I saw how much I could make selling it compared to the heat, noise, electric bill and slower return on investment I decided to sell it. What I made was almost double what I bought it for (and for a lightly used miner) that's how hot the market for Bitcoin miners in May/June 2017 was and still is. 

The Antminer R4 was my favorite Bitmain product because even though it is a powerful miner it is pretty quiet compared to other miners. Why they stopped making it is beyond me but I have a feeling that they wanted to concentrate on making, noisy but modular, Antminer S7's and S9's which they could sell to mining farms by the thousands and hence make a better profit, sort of giving up on the home-oriented miners market.

At any rate, since there was a more immediate profit to be made for me by selling Bitcoin miners as opposed to mining Bitcoin with them I decided to buy a couple Antminer S9 Bitcoin miners from Bitmain and resell them. There was a wait to receive them in June but it was only about a month or so at this time. Buying from the Bitmain company in China was (and is) not a simple process, as most people will tell you who try to buy miners from them - one of the reasons that people are willing to pay more on eBay or Amazon. It is simpler there and less of a hassle. The communication is inefficient with Bitmain, which is understaffed in their sales department. In addition, they are always changing the accepted method of payment, sometimes it is with Bitcoin, sometimes with bank transfer, and now with Bitcoin Cash.

Anyway, eventually I received the two Antminer S9's and wanted to test them to make sure they were operable before I listed them and shipped them to a paying customer. Luckily I had a 1375 watt power supply, so I hooked one up and tried to find it on the network. It seems like this is always difficult when you first turn on a miner and try to find it on your network. When I did find it and assigned a mining pool to it, the machine started mining and I was treated to the trademark Antminer "jet engine" noise that I discovered with my Antminer S7. I don't know if the S9 is louder than the S7 or if they are the same but there is no way I would be keeping either one of these loud ASIC miners since I only have a garage and not a mining farm. Both S9's operated well, hashing away at around 14.5 TH/s. After my brief testing was complete I listed these on eBay and eventually sold them for a 70% profit. Not bad.

Since this fiscal adventure was a success I decided to do it again. However, the next time I wanted to buy some S9's to sell I would have had to wait two months to receive them, so I decided to look elsewhere, if possible, for Bitcoin miners that I would receive sooner. (Apparently other people were having this idea too.) The company I settled on was another Chinese company called Canaan who were making and selling a nice miner called the Avalon 741. Unfortunately, they were just as hard to communicate with as Bitmain, also being woefully understaffed to meet customer demand. But once the back and forth about price and shipping were taken care of and the bank transfer went through, they shipped and I received the machines within two weeks of my initial contact with them. This was probably the last good experience anyone would ever have with them as the company was beset with orders because people wanted and needed miners and Bitmain became even more backlogged. Now Canaan would be backlogged too. 

But for now this first buying experience from Canaan was pretty good. They accepted bank transfer, shipping cost from China was reasonable and I received the machines fairly quickly. This time I bought five machines and controllers and tested one or two of the Bitcoin miners. Within a couple of weeks they all sold and though there was a profit it was significantly less than on the Antminers. The reason the profit was less was that these miners didn't have the same reputation in the mining world as the Antminers do. Also the Avalon 741 hashes at a slower speed than the S9 and so for these reasons it was somewhat less sought after. One of the controllers and miners I had sold did not function properly and were sent back by the customer. After refunding him I determined that one of the hashing boards was inoperable. Canaan support was very helpful and sent me a new hash board which was pretty easy to replace. I was then able to sell the refurbished miner.

The Avalon 741 runs quieter than the Antminer S9. This is because it has only one variable speed fan and because it runs at half the speed of the S9 (7.3 TH/s vs. 14.5 TH/s). It is a good, sturdy and steady Bitcoin miner with a good user interface. It uses a controller (Raspberry Pi) which you have to buy, hook up and power separately and this is unappealing compared to Antminer's onboard controller. I did run the Avalon for about a month and made some pretty good Bitcoin with it, above and beyond electricity cost, so it was a positive experience overall.

As of December 6, 2017 it is almost impossible to get a Bitcoin miner unless you want to pay at least double the price. Bitmain has a 2 to 3 month waiting period and only accepts Bitcoin Cash. Canaan doesn't even bother to sell to individuals any more and their distributors either have a waiting period, no miners to sell or sell out as soon as they put them up for sale. Jhejiang Ebang, who makes the Ebit series of miners, which I will talk about in the next blog posting, is having the same problems. They don't respond to e-mails after you make an order and apparently don't want to deal with individual buyers.

With Bitcoin's precipitous rise in price I think I am back to feeling that it is better to mine for Bitcoin if you want to make money from Bitcoin rather than selling the machines -- that is if you can get your hands on the latest version (or any version) of a Bitcoin ASIC miner. Just buying Bitcoin and holding may indeed be the wisest strategy, even at this point when it is 12,783 dollars for a single Bitcoin.
 
The next blog post will cover my Ebit E9 plus Bitcoin miner experience.

On Bitcoin Mining 7

The Antminer R4 joins me on my Bitcoin mining journey and it is still too early in my experience with this miner to tell anything but a short story about it. But I can say these things right now: It is significantly quieter than any other powerful ASIC miner and it is more electricity efficient than any other miner.

When the R4 is running at 8.7 terahash (TH/s) it still puts out quite a bit of heat using about 950 watts compared to something like 1300 watts for the Antminer S9 (13 TH/s) and the previous model Antminer S7 (4.7 TH/s).

At the moment it is creating the equivalent of about 0.15 Bitcoin per month (in a mining pool) but this will go down at the next difficulty increase.

I really like this machine and though it is not as quiet as the Black Arrow Prospero it is much more powerful, productive, and expensive (unfortunately). Also unfortunately, I see on Bitmain’s website that they have been out of stock for a while and I am wondering if this means they will not produce them anymore. If not, then miners who want a powerful Bitcoin miner that is relatively quiet will have to buy whatever is available on eBay, which is mostly used stock. If you want a powerful miner and don’t care about the noise then get the Antminer S9 which you can get new from Bitmain, on eBay, and on Amazon.

On Bitcoin Mining 6

The next inning in my Bitcoin mining adventure was my ill-fated Bitmain Antminer S7 acquisition. It was ill-fated not because of the perfectly adequate machine that it is but because of what I did with it. Prior to buying it I had no idea how loud this device was (I could hear it outside the garage of my townhouse and so, I figured, could my many closely proximate neighbors.) but I did run it for a while. Finally I decided to run it at a much lower speed so that the fan would run at a much lower (and quieter) speed. This was okay but not optimal. Why have a 4.7 Tera hash bitcoin miner running at a fraction of its design speed?

Then I heard about hosted mining. This is where you send your bitcoin mining computer to someone else who puts it in their building, runs it on their cheaper electricity, and charges a monthly fee that is less than the amount of Bitcoin generated. I did my research on hosting companies and cost and decided on an outfit called ASICSPACE. I and they signed a hosting contract and thus began a nightmare relationship.

I boxed up my Antminer S7 and its EVGA power supply. Both of which cost me $800 back when S7’s were more expensive and there were no S9’s yet. Then I sent the S7 to Tennessee. The company is in Washington state and the pictures on their website of their hosting site are in Washington state so I thought it was odd but I figured maybe they have a satellite site, so I overlooked this little Tennessee detail.

After receiving my miner they told me I didn't send a power supply and of course I told them that I did and described it and sent a picture, etc. After some time they "found it". After this snafu and a period when the owner was "out of town", it took 3 weeks for them to turn the bloody thing on. Once they finally got the miner running it would run for a while and then take days for them to turn it back on or reboot it after it went off. These were days when it wasn’t earning money. Critical time in the Bitcoin mining world. Then it wouldn’t turn on or reboot and that was additional time not mining. Then they stopped trying to turn it on saying that it was only putting out 1/3 of the hashpower. I asked ASICSPACE and Robert Van Kirk, the owner, to return the miner to me after that and he kept stalling or saying that he would and he never did. Then he said that someone else had the miner (!) and I should call him to get it back, only that person never answered the phone.

So almost a year later I still don’t have my miner or power supply back which I basically consider as theft of my property. The company is supposedly defunct but their website is still up, so I am worried that someone else may be taken for a ride by this guy.

My advice to you if you are considering having your miner hosted . . . DON’T!! Try and deal with it yourself.

In the next installment I’ll talk about the Antminer R4.

On Bitcoin Mining 5

It turned out that we would not be in my sister-in-law's house as long as previously thought. They were returning home and we needed to move out to a townhouse that we owned by January. This meant that I would not be able to bring the BFL Monarchs with us. For one thing they were too loud for a townhouse environment and too hot. They were also not very efficient in terms of electricity consumption. They are rated by BFL for 0.65 to 0.85 watts/GH but I measured them as using close to 1 watt per Giga hash including the power supply and the necessary laptop.

Bitmain Antminer U3 version 2

Looking for quiet, townhouse friendly miners, in October I bought two Bitmain Antminer U3 miners. This ASIC miner is very similar to the Rockminer R-box 1 (37GH/s) miners. The U3 however runs at 55 to 62 GH/s. Like the older Rockminer, the U3 is basically silent and put out little heat while using about 50 watts of power (plus wattage of attached computer). The problem is that every day or so these miners would become "zombies" meaning that they would stop working. This requires a hard reboot of the device (unplugging and re-plugging) and restarting the mining software. It's a hassle and not on a schedule of any kind so you don't know when you'll have to do it. So as quiet as this was, the fact that it had a problem like this and that I felt the hashrate was too low I kept looking for a better solution.

The better solution in my situation was the Black Arrow Prospero X-1 (X-1.5). The X-1 hashes at 100 GH/s or better and the X-1.5 hashes at 140 to 190 GH/s. This miner is unique among ASIC miners - for one thing it has a large fan which dissipates the generated heat very quietly and effectively. For another thing it has an Android-based touch screen for interfacing with the miner. The miner is also WIFI capable which means that you can place it anywhere in the house and it doesn't need an ethernet cable or a computer attached to it to run the mining software. It is truly a stand-alone device. Perfect! As it got closer to moving day (again!) I sold the two Monarchs which turned out to be pretty solid hashers - if a bit inefficient - and bought two Black Arrow Prospero X-1.5s. I also sold one Antminer U3 and kept one in the box as a backup. I ran the two Prosperos near the dining room in the townhouse for most of the winter and spring of 2016 and appreciated their silence and their heat generation. 

The nice thing about mining for Bitcoin at home is that for part of the year the heat that Bitcoin miners generate can (and is) used to heat your living space. One hundred percent of the heat generated will go into the air in your home. For instance, if my two Prosperos raised the temperature of the downstairs portion of my townhouse by two degrees Fahrenheit, then that is two degrees that didn't have to be heated by the furnace (electric blower and gas fueled) thus saving that much electricity and gas from being used to heat our home. This means that the efficiency of the miner doesn't matter very much in the winter or on cold days in the spring and fall because you are basically running a heater that is mining Bitcoin. It's another story when the hot weather comes but the efficiency of Bitcoin miners is going to be better than rated over the course of a year if they are used in environments where their heat is used. (Now if they could make Bitcoin miners that generated cold air we'd be all set for the summer!)

I'll cover my experience with Bitmain's Antminer S7 in the next On Bitcoin Mining.