DualMiner USB 2 Review

Following the success of USB DualMiner we tested recently, the manufacturer has launched a new version that I had the chance to try exclusively for several weeks. I invite you to read my test of the first generation capable of mining Bitcoin and Litecoin at the same time for the detail of the product. This criticism will focus only on the differences USB DualMiner 2.


Very similar to its big brother, the USB 2 DualMiner largely reproduces the look and components.Always equipped with a chip Gridseed GC3355 able to accomplish 70kH / s in Scrypt mode, it still has an aluminum heat sink, but this time it is blue. Hence the small name “Sapphire Miner” that you can see on the 800zipcodes.

It is not very well named because it does not have two modes. This model exclusively mines the alternative cryptomagnet of Scrypt type. New algorithm types like Scrypt-N and Scrypt-Jane are not supported because they require much more RAM, especially in the future when their algorithm becomes complicated.

Absence therefore of the small switch B / L, although it seems to have two LEDs, only one lights up during its use.


  • Format USB flash drive powered by USB port
  • One mode: Scrypt
  • LTC Mode: 70kH / s (1.5W)


I noticed during my various prospecting sessions that this new model releases a little less heat than the old one. I am talking here about 2 or 3 ° C but all the same, we will take all the optimizations that the manufacturer can give us!

Having only one mode, the DualMiner USB 2 can only undermine the Scrypt cryptomy, at a promised speed of 70kH / s. As you can see, with a good pool it’s very easy to reach 70kH / s and even a little more.

During this 44-minute session, I got an average speed of 79.2kH / s. Also note the number of hardware errors (HW) to 0. During a 23-hour session, I also had 0 hardware errors.

The profitability?

If we take the Litecoin currency and buy a pack of 10 of these DualMiner USB 2. The acquisition cost is about $ 600 including a good USB hub and postage.

We talk about a power of about 790kH / s and a current consumption of about 15W for the DualMiner USB 2 and a little more for the hub. Let’s say 20W for the calculation. At the current Litecoin price at $ 11.44, we will need 360 days to make the purchases profitable and reach the deficit 0.

So in a year, the profits will start! Obviously the market is what it is, it is very possible that you can make more money if the Litecoin increases during the year. And also, if the difficulty increases, you will make less money.

The same applies if you mined Dogecoin or other currency based on the Scrypt protocol. These currencies are even more volatile and as the vast majority is worth almost nothing, they are very likely to rise in value!

Positive and negative

Good points

  • Product Stability
  • Promised Efficacy Exceeded
  • Little heat

Negative points

  • Mixing Product Name
  • BTC deceptive logo display
  • Expensive to the unit


Like the USB DualMiner first of its name, the USB 2 DualMiner reliable, efficient and very easy to use.On the other hand, the name is mixing, because it no longer dual mode Bitcoin and Litecoin, only one mode is available. Moreover, to print the logos of BTC and LTC on the key is also problematic ….

Finally, a single key is slightly cheaper than the previous version, but a substantial discount appears when you order 10. A key costs $ 82 and in batch of 10, the unit cost becomes $ 45, a discount of almost 50 %!

Are all this is a great product to learn a little more about the wonderful world of crypto money prospecting! Is it cost effective in small quantities? No, but there is always the possibility that the money you mine will gain value!