BITMAIN ANTMINER U2 2Gh/s USB Bitcoin ASIC Miner. Overclockable

I was curious about BitCoin Mining when I came across this product on Amazon. To tell you the truth I was a little concerned at first buying any product with it electronics exposed as this USB ASIC had no back cover. All I can tell you is that it is well built and the heat sink does cover the other side of the circuit board giving it a rugged feeling. The product does work very well, just I forewarn you it does not come with any drivers or instructions on how to use it. I am using it to mine BitCoins on Windows 8 and it is not plug and play. You will have to do your own research and download its drivers manually, you will also have to figure which mining software and pools works with it. Once all that was figured out the product was in an operational condition it was running at 1.5 GH/s, then I had to go in the software to tweak the settings to get it running at the advertised 2 GH/s. Even though this product does run a little faster than its predecessors it is still considered an entry level mining gear, and like computers you will always be able to get faster ASICs for the same price as time goes on. I did like the product very much but do not expect to buy it and get rich of it fast. Running a profitable BitCoin mining gear is hard, time consuming, speculative and can be very expensive. I have yet to find a single person that says “I make a living out of mining BitCoins” every review I have read on the internet so far says “I started mining Crypto Currencies and later ended up selling my BitCoins and Gear on E-bay for a loss”. There might be a few people that have figured the system out, but I have yet to hear from any of them publicly and read how they did it in details. Buying a few of those ASIC’s can be fun for testing and experimentation especially that they can be purchased under $50, on the other end of the spectrum some mining gear rigs can run in the $12,000 or more (Of course they also have a very high Hash Rate). As for the product I think it is very nice I am really enjoying it and I am thinking of buying a few more. The hash Rate on the Product can be adjusted as in over or under clocking it, and if you set it right you can even have it running without producing too much heat. So have fun while it lasts.

I got one of these mostly because I am curious how well they work.1) There are absolutely no directions so you are on your own. It is not too hard to get it working though. It took me about 20 minutes to figure where to get a driver; download it; install and get it working without overclocking.2) It runs hot even without overclocking so I am not too keen on running it even hotter.3) It does about 1.6 Gh/s with the driver I got which is the U1 driver since I couldn't find a U2 driver.I say it is not bad so far. Don't expect miracles and you won't be disappointed.However I doubt that it will make any real money since the rate of mining with one of these is about 0.005 bitcoins per month with today's difficulty. As we know the rate will keep dropping so in about 200 months I will have a bitcoin :-)On the other hand it makes a lot of heat and where I live is pretty cold. If you take the free heat into account then a bunch of these may be a self funding heater.

Will not work with bfgminer or cgminer. I ordered this as a test unit and am not happy. It works with BitMinter but if you want to mine something other than Bitcoin I recommend trying something else.

After my experience with my three U1s I decided to test these out, since they claimed 2GH/s stock and had these enormous heat sinks. Problem is, for some reason mine keep going into Zombie mode on CGMiner, and sometime hotplug themselves! I don't know how that keeps happening, but it's been frustrating.Also, if you run them with your U1s and they're at their stock 1.6GH/s, your U2s will be going that speed too. I don't mind much, since at this point this is just toying around (with the Bitcoin network difficulty at 7 Billion at time of my writing this it's almost stupid to buy just one of these things if you want any real profit).. I don't expect to be raking it in.On that point, the Bitcoin difficulty is skyrocketing. If you want to get in on it, you may be too late. But if you want to take the risk, you may want to buy several of these things. And a big fan. These will get extremely hot without active airflow.These are much cheaper than their U1 counterparts, and much faster than the ASICMiner Block Erupters I've used in times past. They're about the best you can get at this time in terms of USB powered miners (for the price)... There are some chips that can outrun these, but why bother spending 90 bucks on something you can get more speed for in two units for half the price?My only other complaint, as others have stated, is the heat sinks make it harder to fit these on certain USB hubs.So...Pros-Speedy-small-very economical (more so than U1s or BEs)Cons-Screwy Hotplugging (maybe only for me...)-they still can burn you even with the big heat sinks-U1s set at stock on same rig will slow them down-you won't strike it rich if you only buy one-heat sinks are pretty big, can interfere with some setupsThey're an interesting product, just keep these things in mind, whether you're upgrading, or just starting out.