Archive for the ‘Tests and Reviews’ Category


We have been testing the new Next Generation of ZeusMiner Scrypt ASICs (Zeus Lightning X6, Zeus Thunder X6 and the Zeus Hurricane X6) for a few days already and have already reported our very first impressions. Now we have some more interesting findings and information available to share with you based on our continuing tests, this time we are going to focus on the power usage of the new X6 series of miners that are supposed to be more power efficient – their key feature. What Zeus has done with their ZeusMiner X6 Scrypt ASICs is essentially lowering the operating voltage and power and thus achieving lower power consumption. If this was not also combined with new lower prices as well the new X6 miners would not be so interesting, but their new lower prices (even though you cannot yet take advantage from them directly buying from Zeus due to their pre-order 1+1 bonus promotion) at their distributors are actually quite attractive combined with the lower power consumption.


We have already discovered that the best operating frequencies of the new miners (there is no recommended frequency published on the official website for the advertised hashrates) seems to be at about 245-250 MHz for the ZeusMiner Thunder X6 and the ZeusMiner Hurricane X6, however the ZeusMiner Lightning X6 does not appear to be handling so well at these operating frequencies. In fact even at 230-235 MHz we are still seeing HW error rate of about 10% or more which in our opinion is a bit too high, but going lower in terms of operating frequency does lead to decrease in the hasrate of about 40-42 MHS. So what is the reason for this difference? We have already suspected that the operating voltage of the Lightning X6 is even lower than what it is on the smaller Thunder X6 and Hurricane X6, but checking out the actual power consumption of the miners and opening them up to inspect them has confirmed our suspicion. Zeus has even made it very easy to spot the difference by putting a label of the actual voltage used by each board and as you can see on the photos, the Thunder and Hurricane X6 miners have 1.1V used and the Lightning X6 has the chip voltage lowered to 1.05V. This is probably done in order to get the total power usage of the Scrypt ASIC miner below 1 KW, but as a result you will need to use an operating frequency of about 220 MHz for low HW error rate and the hashrate you can expect is more like 36-38 MHS and not 40-42 MHs. But this is not the only concern we have with the new miners as Zeus has done some more optimizations, probably with the idea to cut costs further, that we do not like very much.


We are stating with the power usage of the 9-10 MHS ZeusMiner Hurricane X6, according to the official specifications is should use about 230W of power and a good 250W power supply is recommended, though you probably will not be able to find a 250-300W 80 Plus Gold or Platinum PSU, you can use a more powerful one. Running the Hurricane X6 miner at 250 MHz operating frequency we have measured an actual power consumption of about 276-278 Watts. This is a bit higher than the claimed power usage, and though it may not be such a big of a deal, when you consider that the miner is powered via a single 6-pin PCI-E power connector this raises some concerns.


Moving to the power usage of the 18-20 MHS ZeusMiner Thunder X6 we see on the official website a power consumption of 450W claimed with a good quality 500W power supply recommended. Our tests have shown a different number running the miner at 250 MHz, the number we got is more like 542-546 Watts and that is like 100W more. This is essentially double the power usage of the Hurricane X6 as the Thunder X6 does have twice the number of chips inside, so it is to be expected if both miner run at the same frequency and use the same voltage for the ASIC chips.


Next up is the power usage we have measured for the 40-42 MHS ZeusMiner Lightning X6 Scrypt ASIC. The officially cited power consumption is 980W with a good 1200W PSU as a recommendation. Our tests have shown actual power consumption for the miner at just about 906-914W at an operating frequency of 230 MHz and about 970W measured at the wall (taking into account the PSU efficiency). Here the power consumption is not double the one from the Thunder X6 even though the number of chips inside is doubled and the reason for that is the lower voltage of the chips that is 1.05V instead of 1.1V. It has been lowered as otherwise the actual power consumption should’ve been something like 1100 Watts at 1.1V.

We’ve confirmed that the power consumption numbers on the ZeusMiner website are not entirely correct, they are lower on the smaller miners and higher ton the top miner compared to what we have measured. That however is not the actual problem here, the problem and the thing we did not like much is the fact that Zeus has reduced in half the number of PCI-E power connectors available to power the new miners. As you should know by specifications power supplies are designed to supply 75W over the 6-pin PCI-E power connector and 150W over the 8-pin PCI-E power, even though the actual hardware is usually capable of supporting higher power as these were originally designed to power video cards. The 18 AWG wires used normally in most power supplies (some use 16 AWG) and the connectors should be capable of 8-10A over a single 12V wire and with 3x 12V lines on both 6-pin and 8-pin PCI-E power connectors this should in theory easily cover up to 300W. The problem however comes from the fact that PSU manufacturers are not required to design their products to handle so much power over a single rail for PCI-E power connector and most don’t do it, even if they do supply some extra over the 75W/150W requirements they have. So 300W per single 6-pin PCI-E power line can be a bit overkill for an ASIC miner running 24/7 and the easiest way to confirm that without special equipment is to check the wire by touching it after the miner is started. if it quickly gets hot, then things are definitely not Ok, though it is just a bit warmer to the touch it might be fine.

Having 278 Watts of power provided to the ZeusMiner Hurricane X6 over a single 6-pin PCI-E power connector is something that raises some concerns, so you should be extra careful what power supply you are using. With the ZeusMiner Thunder X6 the situation is very similar, though here you have two 6-pin PCI-E power connectors with each transferring about 273 Watts of power. Things are a bit better with the ZeusMiner Lightning X6 that has 4x 6-pin PCI-E power connectors with each one getting just about 228.5 Watts. So what ZeusMiner should have done is actually double the number of PCI-E power connectors on their miner to distribute power more evenly to each board and to lower the load on each of the PCI-E power lines. We do recommend to be extra cautions when you are setting up the new miners and check the cables to make sure that they are not getting very host quickly after you turn on the miner as this may potentially lead to damage of the hardware – both the miner and the power supply and this is something that you will want to avoid.


Silver Fish is a Chinese company making Scrypt ASIC miners based on 55nm Scrypt ASIC chips that they have apparently developed in-house called SF300K01 – 55nm chips with lower power consumption and rated at 625 KHS at 7W per chip. The main target for their Srypt ASIC miners available in the smaller Blade version we tested and the bigger 70 MHS models that Silver Fish makes is the Chinese market as they do not even have an English version of their official website. Their Scrypt ASIC miners, especially the smaller 25-28 MHS Silver Fish Blade miner, are already finding their way in other parts of the world and that is precisely why we have decided to get a unit and review it. It is certainly an interesting product with some specifics that you can also consider as disadvantages if you compare to what we have used with traditional ASIC devices, but they are not necessarily such. In fact the approach that Silver Fish has taken into their products is quite interesting even though it might be considered somewhat limiting the user.


The Silver Fish Blade consists of two independent PCBs, each with 20 SF300K01 Scyrpt ASIC chips grouped in blocks of 4 with independent power blocks. So the whole Blade miner has 40 chips for a total hashrate of about 25-28 MHS for mining Scrypt crypto currencies such as Litecoin. The device is cooled by a single large 120mm Delta fan that is quite noisy, even though it apparently should be controlled through a PWM from the device based on the reported temperature from the available onboard sensors. The reason for the high noise level is probably a direct result from the open design of the device that certainly is not optimal for proper cooling with lower RPM of the fan, though apparently the device does manage to keep things in normal operating temperatures even this way.


Notice that each of the PCBs is completely independent and has a single 6-pin PCI-E power connector as well as two LAN ports. The advertised power usage at wall for about 28 MHS performance is 470 Watts, meaning that each PCB needs about 235W, but we’ll get to the actual power usage in a bit. The LAN connectors on the back are used to connect the two PCBs together and you only need one cable to go to a computer or a network appliance in order for your device to be accessible from the mining software. According to Silver Fish this approach for connection allows for up to 100 PCBs to be connected together with a single connection to your network, so apparently these miners have been designed to be used and deployed in larger mining farms and nor for small home-based miners.


The software that is used to control and mine Scrypt with the Silver Fish Blade miners is only Windows-based and needs to be run on a PC that is connected on the same network that the Scrypt ASIC miner is connected in. The software should be able to automatically find the miners in the network and start mining with the pools you have set to be used, so it is pretty straight forward thing to do. Unfortunately the latest version of the software R3.04 is still not available in English, though you should be able to use the previous SFMiner 2.1 English just fine, even though the configuration utility inside it is not translated in English.


A quick look on the actual power usage of the Silver Fish Blade miner supposedly running at 28 MHS with a 1200W power supply attached to the miner. Apparently the actual power consumption is is around 430W and thanks to the fact that we are using a good power supply at its sweet spot in terms of efficiency (about 99%) the power usage at the wall is just slightly higher. With a not so good power supply you can probably expect to get close to the 470W advertised as actual power usage at the wall. With this power usage the Silver Fish Blade is probably the most power efficient 55nm-based Scrypt ASIC miner currently available on the market, beating even the new lower power usage ZeusMiner models.


We’ve already mentioned that we do not like that much the open design of the Silver Fish Blade miner, even though apparently it has no problems with keeping the things in acceptable temperature levels. As you can see from the thermal images we’ve captured of the miner in action the temperature level increases as we get further away from the cooling fan and the temperature difference can be higher than about 10 degrees between the two ends of the PCBs. If you want to improve things with the cooling you can easily create a case for the miner with handy material in order to improve the airflow and thus the cooling efficiency of the device. What we could not find a way to do is to overclock the miner to see if we can squeeze some more performance without significant increase in power usage.


Time to see what is the performance we are getting with the Silver Fish Blade Scrypt ASIC miner, officially the manufacturer rates these at 25 MHS (40 x 625 KHS), but the unit we got was actually rated at 28 MHS, so apparently slightly overclocked. We have tested the poolside performance at the LTC Rabbit Scrypt mining pool as it has recently opened new fixed difficulty ports for Scrypt ASIC miners. The results we’ve got have shown hashrate peaking at a bit over 28 MHS and with an average of about 27.4 MHS, pretty similar to what the software used for control and mining also reports in terms of performance. Trying out with other Scrypt mining pools such as CoinKing for example has shown us pretty similar results, or you can expect an average hashrate of a bit less than 28 MHs.

So what is our conclusion about the Silver Fish Blade Scrypt ASIC miner? There are some things that we did not like such as the open case design and not so efficient and nosier cooling or the availability only of Windows-based software that is not completely translated in English. As well as some things that we liked, such as the compact size, the lower power usage and the network connectivity that allows for easy scalability. Good performance and stable operation, combined with lower power usage than competing 55nm-based alternatives makes this an interesting option if you manage to get a good deal in terms of price. If you manage to find these at sub $900-1000 USD price they may still be a good investment, even though with the current network difficulty and price of LTC you should still consider carefully.


It seems that the currently most affordable in terms of price Bitcoin cloud mining services – PBMining and Bitcoin Cloud Services might have some new competition. By new we really mean new, as a new BTC cloud mining service was apparently very recently launched in Sweden called Lunamine. We normally do not review services that were just launched and usually give them some time to see if they are not just some sort of a new scam and to give them some time to fix bugs and improve the features they offer before reviewing them, however we were asked by readers to check this new service out and we have decided to do so.


What makes this new service interesting, and by new we really mean new as their domain name was registered on 30th June this year or a little over a week ago, is the fact that they claim to offer pretty much the best price per GHS for Bitcoin cloud mining. They even manage to beat some other services that were fighting to offer the best price to customers by a bit, like the two we already mentioned. The current rate stated on their website is 0.0025 BTC per GHs, but the real rate can be slightly higher due to the variance in BTC exchange rate. They accept payments in BTC only, though the contract prices are listed in USD prices and they apparently calculate how much BTC you need to pay with the current exchange rate for the contract you have chosen based on the USD price. Initially Lunamine has launched a free 7 day trial with 10 GHS for people to try their service, but apparently this was very quickly stopped due to people abusing it (according to the official information published). So at the moment you can purchase a contract of minimum 100 GHS for $160 USD or about 0.254 BTC, or go for a 1 THS contract for $1400 USD or about 2.2229 BTC (you can get multiple of these as well). We have chosen the 100 GHS contract for our testing and yesterday when we have purchased it e had to pay 0.25234804 BTC for it or about 0.00252 BTC per GHs.

You will probably notice that there is no term period cited for the contracts duration, something that is a bit confusing as it says “Lifetime validity” and “No operational fees” when you are about to purchase a contract. There is a catch though, as Lifetime validity actually means until the hashrate purchased by you actually brings some profit for you when you pay for the electricity cost. Yes, there may be “No operational fees”, however you need to pay fee for electricity used and the rate is $0.0032 per GHS per day, and so for a 100 GHS contract you have to pay $0.32 USD a day for electricity and the rest of the mined coins you get as profit. Doing a quick calculation shows that at the moment you can mine around 0.00299 BTC per day with 100 GHS hashrate or your daily profit will be around $1.85 USD minus the $0.32 USD fee for electricity or around $1.50 USD with the current network difficulty of Bitcoin. This would take around 106 days or about three months and a half for you to break even on your investment and actually start earning on to of what you have invested if the conditions remain the same as in the current moment… and they will not be as the network difficulty will continue to rise. So do have in mind that as in about three months and a half from now if the network difficulty continues to rise with 10% you will be making about half of what you can currently mine with the same hashrate and the fee for the used power will remain the same. If you remain with only 100 GHS the lifetime of this contract will be roughly about 230-240 days or about 8 months before the mined coins will not be able to cover the electricity fee, that is if the price of Bitcon remains the same and the network difficulty continues to increase by about 10% each time, so not that accurate calculation.


After we have purchased our contract it took about an hour for the payment to be processed and in about two hours the contract was activated, though this may take up to 12 hours according to the service description. Another thing to note is that while your mined coins get credited in your account, there is no automatic daily or weekly payout, you need to request the payout manually and in order to do so you need to already have accumulated at least 0.01 BTC. Furthermore since the payouts are apparently processed manually it can take up to 48 hours for your request to be fulfilled again according to the official information published about the service. We haven’t tried withdrawing yet as we’ve just started testing the service and have not yet generated enough BTC in order to be able to request a withdraw of the mined coins.

An important word of advice though, we have just started testing this service and since the service is really very new we do recommend serious caution! If you are interested in trying it out always start with a minimum investment and with something that you can afford to loose if things go bad. We are going to continue using the service and will be reporting how things progress with it as well as our own experience using the service.

For more information about Lunamine’s Bitcoin Cloud Mining Services currently offered…