BFL Monarch - 28nm Water Cooled Bitcoin Miner - In Hand - Ready to Ship!

Product performs the way it should. Buyer be ware. . . you need to make sure your getting a 700GH/s unit. The ad says one thing and the indvidual sellers might be selling you a ~545 GH/s unit instead. I received mine and it was a 545 GH/s unit. Not that I am complaining because the power usage is still way low than any other device I have in place. The power supply really makes the difference. DO NOT BE CHEAP ON THE POWER SUPPLY!!!! Get a really good power supply. I am using an EVGA 750 Watt. The orginal power supply I tried was a 650 Watt piece of junk and it really wasn't rated for the full 650 Watts it over heated the power supply. I changed it out to the EVGA and the power is even lower than before.

I purchased a used unit on eBay, but I thought it'd be worth a review for others interested in this product.My unit is rated from the factory for 750GH/s. In ~2hr shifts I get anywhere from 699GH/s to 760GH/s. I did get 801GH/s once, but it's generally closer to the 720-740 range running around 68-70C temp in an ambient between 25-30C.I was using cgminer before, but this requires bfgminer. So I have this running on one machine and my other hardware on a different machine running cgminer. It came with the bfgminer software on a CD, so I just had to copy the folder to my hard drive, create a batch file with my login info, add to my startup directory and good to go.This miner is very quiet. The water cooling works well and the fan provided is fairly silent (especially compared to the water cooling fans on my Habanero). As expected it's burning lots of power for processing so the fan output is fairly warm.My biggest complaint is that I wish it had a fully enclosed box instead of the weird-shaped sled. I have it installed on a shelf in a rack with other equipment and I want to make sure nothing contacts the parts and shorts them out, which is kind of hard to do with everything exposed.For a power supply I bought a dedicated 12V 50A (600W) supply instead of a computer power supply and made my own custom connectors. It also has an output voltage adjustment so I can adjust the voltage to get a nominal 12V at the Monarch connectors. In retrospect I probably should have got a 60A supply so I'd have more headroom, but it so far has been running fine 24/7 with no issues and I don't plan on overclocking. I have since bought a Sentley 750W power supply which is also much quieter.Some people don't understand how to select a proper power supply, so I'll add some useful notes here:- You need check the amount of power provided on the 12V rail. Multiply voltage (12V) times current (xxA) to get the power available on that rail. Here's some useful values:- 50A = 600W, 62.5A = 750W, 70.8A = 850W- Get a supply with a single 12V rail. Some supplies actually have multiple 12V sources, which aren't exactly 12V. For example one could be 11.9V and another could be 12.1V. If you connect both of these to the same miner you potentially create a current loop which at a minimum wastes power and at worst blows something up. Some miners (like the Chilimining Habanero) state it's OK to do this since each connector is a separate power rail on the miner board.- Cabling is important! You need at least 16 gauge wiring on the supply. Even then at 600W the 16GA wires will get warm. The smaller the gauge number, the thicker the wire, the better. You want a supply with at least three PCIE connectors. Ideally each one would be straight from the supply, but in a lot of cases they string two on the same wires. This seems to be OK, but not ideal. Also the shorter the wire length the better. No one specs this though.- Do NOT use splitters that take a single (or even double) 16 gauge wires and split it out to an entire PCIE connector. It's a fire hazard!

Most folks looking at this are probably aware of Butterfly Lab's troubled history. I gather that they are (slowly) digging their way out of that hole with the supervision of the courts and the FTC. For those who have taken a financial hit, you have my sincere sympathy. But I am here to review the product, not history, so let's press on.When I received an email from BFL offering these miners here on Amazon at a good price, I crossed my fingers and ordered one. Naturally, I worried a bit, but I relied on Amazon to back me up if there was a problem with the order.To my pleasant surprise, the Monarch shipped immediately and was received a couple of days later.Since receiving the Monarch it has been up and running 24/7. It delivers at the advertised hash rate, and has done so reliably. I like the water cooling, and power consumption has been reasonable. It does produce a fair bit of heat, and a moderate amount of noise. Mechanically, the sled could be a little better. The intermediate (small) power connector for the fan is scary, as it is prone to coming loose when disturbed, which could have catastrophic consequences. I strongly recommend that you tape the connector, and also strain relieve it with tape or a Ty-rap.Overall I would say this is a decent product, but I have also ordered and Antminer S5, so when it arrives I will be interested to see how it compares. The S5 is supposed to be faster, but what matters most is the hash/watt ratio. Whichever unit generates the most calculations for my electricity dollar is the one I will be purchasing for the foreseeable future.I am running a data logger on the power consumption, so when I have some comparisons to offer, I'll try to remember to update the review.Edit: After running the Monarch alongside the Antminer S5, I wanted to let folks know that while the S5 is roughly twice as fast, it is also more than twice as loud. If you plan on running your miner in your living space, I suggest the Monarch. If you can set up in a basement or garage, the S5 is the way to go. It believe it would be easier to bear the noise of two Monarchs than one S5.

I love this miner. I have several in a rack mount at the data center and one in the bedroom for those nights the polar vortex brings the cold air down. Plus less than 600 watt at the psu.

Friends don't let friends buy Butterfly Labs products.Do a Google search for "Federal Trade Commission v. BF Labs Inc" for some revealing information on their business practices.