Archive for the ‘Tests and Reviews’ Category


As the popularity of Bitcoin and other crypto currencies continues to rise more and more new services appear, including various ones that offer you to earn Bitcoins by playing them for free. Initially this may sound like a good idea, to spends some time playing a simple game for example and earn some Bitcoins in return, but things are actually not that easy and of course there is a catch. The developers of games and apps that seem to give out free Bitcoins to people playing them are not running a charity here, it is a business that runs on a very simple and proven model that works and in the end they end up making profit by “giving BTC for free”. How is that possible and what is the catch and can you actually make some Bitcoins for free? We are going to answer these questions using the free Bitcoin game BTC Flow as a real world example to demonstrate how things work.


The general idea here is that we have a simple web-based game where you need to only enter your Bitcoin wallet address to start playing and collecting Bitcoins by operating a virtual business. The game is designed in a way that you need to wait a certain period of time for a fraction of coins to collect and then to claim them and you need to keep claiming them over and over again until you reach a certain limit before you can actually withdraw them. By default you have an earning rate of 0.0000015 BTC per minute and you need to keep claiming the accumulated satoshi’s each time they reach a maximum of 0.000012 BTC or before that. When they reach that amount you stop getting new coins until you claim them and in order to do that you need to click on a button and enter a captcha and then you start collecting more. The idea here is that you will not just leave your computer running with the browser open and earn Bitcoins just from that, you need to be active pretty much all the time. The catch here is that you need to reach 0.01 BTC collected before you can request the BTC you have collected in the game to be sent to you and that is actually not an easy task, so lets do some math to see why:

You are earning: 0.00000150 BTC per minute
The maximum collected before claiming manually: 0.00001200 BTC
Interval needed to manually claim to continue earning: 8 minutes
Number of times you need to collect accumulated coins to reach 0.01 BTC: ~833
Time needed to reach 0.01000000 BTC to get paid your earned coins: ~111 hours
What you would actually have earned in USD in almost 5 days of non-stop play: ~$2.5 USD
Total BTC you can earn playing non-stop for one full month (impossible): about 0.06 BTC

So after doing the math you see there is no much point to spend almost 5 days 24/7 non-stop earning free Bitcoins playing a game that will reward you with just about $2.5 USD for the time spent. In the end this seems to be really a waste of time for nothing, and if you don’t calculate things you may start playing just to give up some minutes or hours after that in which case the game operator does not loose anything as you will not be able to withdraw any coins. If you don’t give up easily and are very persistent and continue and spend 2-3 weeks just to get a single payout out of the game as playing non-stop for 5 days is not something that would do you will realize that this time was literally wasted seeing what is the actual return.


Here however we get an attractive option that makes the game no longer free – the ability to upgrade your business earning you free Bitcoins by spending some actual BTC that you already own with the idea to earn back more. This is the catch that actually brings the profit to the service operator as unless you do that the game is not earning anything, but it is hardly loosing any Bitcoins that are given for free either. When you get discouraged by the calculations above or after playing for a bit and you want to actually earn something you see that the only way is to deposit some coins to speedup your earning level. You get multiple levels of upgrade that cost you between 0.05 BTC to 100 BTC that supposedly make it easy not only to get back your investment, but earn much more, or at least that is what it may seem at first sight. So let us see what happens with the math after you decide to pay 0.05 BTC for an upgrade:

You are earning: 0.00000600 BTC per minute
The maximum collected before claiming manually: 0.00018000 BTC
Interval needed to manually claim to continue earning: 30 minutes
Number of times you need to collect accumulated coins to reach 0.01 BTC: ~56
Time needed to reach 0.01000000 BTC to get paid your earned coins: ~28 hours
What you would actually have earned in USD in 1 day plus of non-stop play: ~$2.5 USD
Total BTC you can earn playing non-stop for one full month (impossible): about 0.26 BTC

Things do seem to look a bit better now, but in reality the situation is not much different. You need over 1 day of non-stop playing just to reach the minimum withdraw limit, and close to 6 days of non-stop playing just to cover what you have invested in the form of the 0.5 BTC to actually increase your earning rate. You also need to claim your earnings every 30 minutes instead of every 8, so it is not much more convenient as your attention is required every half an hour. And the upgrades do come with another catch, they are not indefinite, but only last for a certain period of time and that changes things. If after an upgrade you might earn in theory maximum 0.26 BTC playing non-stop for 1 month, something that is hardly even possible, but the theoretical maximum earnings will be close to 0.17 BTC instead as you only get the upgrade for a bit less than 20 days. That is possible only if you play non-stop and do not waste any time for sleeping or other things, and if you spend 8 hours a day (a more reasonable and actually doable thing) carefully monitoring the game and playing it in about 20 days you would barely be able to get back your 0.05 BTC that you invested and maybe a bit less than another BTC cent on top.

Is it worth to spend so much time and effort just to end up with $2 USD actually earned? In fact a lot of people that would spend some Bitcoins for upgrades to try to earn more will easily give up or will play in a way that they will not be even able to earn back what they have spent as a deposit. And even if some that are very determined and strong willed players do end up earning some BTC the number of people that will just give up and have spent some coins for upgrades will be higher. So in the end it is simple math and human psychology that makes such games and services offering free Bitcoins profitable for their operators and not for the users that are trying to earn something from them. You don’t believe us, why don’t you give it a try and see for yourself?


We have gotten an ASUS GeForce GTX 960 STRIX to test GPU mining with it and also checked the power usage with the various algorithms supported by the latest ccMiner fork from SP that is optimized for Nvidia Maxwell GPUs. The ASUS STRIX is one of the GTX 960 video cards out there with the highest factory overclock, so it is supposed to provide higher performance as compared to the more reference Palit GTX 960 OC card that we have tested recently. Do note that the Nvidia rated TDP of the GTX 960 GPUs is 120 Watts and it seems that the reference cards that are not factory overclocked are more like in the 100W of power usage and the higher clocked models such as the ASUS STRIX GTX 960 do manage to go up to the 120 Watts power consumption mark.


We have used the ccMiner 1.5.31-git Fork by SP for Maxwell, the same version that we used a few days ago, so that we can compare performance with the GTX 750 Ti and the GTX 960 OC card from Palit to the results that the ASUS STRIX card offers. There is a newer version of the ccMiner fork from SP already available that fixes the NIST5 support, though there is not much difference in the performance in the Lyra2 algorithm on the GTX 960 as compared to GTX 750 Ti. Also the Blake, Blakecoin and Penta algorithms that rely a lot on the CPU and do not use much of GPU resources do not seem to provide much better results on the more overclocked ASUS cards. Other than that the ASUS STRIX card does provide some extra hashrate over the Palit GTX 960 and thanks to the higher clocks factory preset for the ASUS its performance gets closer to 2x the hashrate provided from a reference GTX 750 Ti GPU that is not factory overclocked.


Today Nvidia has introduced a new mid-range GPU based on their latest Maxwell architecture – the GeForce GTX 960. Specifications wise the new GTX 960 is kind of half the parameters of the GTX 980 at about half the price, but it is actually more interesting as an alternative to GTX 750 Ti in our opinion. The Nvidia GeForce GTX 960 GPUs should provide roughly 1.5x to 2x the performance of a GTX 750 Ti being slightly more expensive and with 120W TDP according to the official specifications. We have managed to get our hands on one GeForce GTX 960 from Palit, their reference-like design though it is still slightly overclocked version, but the lowest and cheapest version that they currently offer and have decided to compare it to the performance of a reference GTX 750 Ti card with no factory overclocking to see the difference in performance.


We have used the latest ccMiner 1.5.31-git Fork by SP for Maxwell to test on both GPUs and you can see the results in the table above. As expected the performance result from the GTX 960 we are seeing are in the range 1.5x-2x the ones that GTX 750 Ti provides. With a more serious factory overclocked GTX 960 results more to the 2x can be observed as compared to a reference non overclocked GTX 750 Ti GPU. There were however a few weird things that we have noticed and also the reason why there are no results from all of the supported algorithms listed in the table. Lyra2 for example performs worse on GTX 960 than on GTX 750 Ti, it probably needs some optimizations to show the maximum potential that the GTX 960 can offer. NIST5 seems to be broken in the latest ccMiner fork as it did not properly work on any of the Maxwell cards, the Blake, Blakecoin and Penta algorithms provided too weird results and very significant difference between the two cards. So we have decided not to include them until further investigation on why the results are so strange and different for the two GPUs. Anyway, it seems that the GTX 960 could be an alternative solution for GPU mining instead of the GTX 750 Ti for mining rigs that use multiple video cards. That is if you consider investing in GPU mining rigs for mining crypto coins with the idea not to mine for profit at the moment, but to keep the mined coins expecting better times to trade them as currently GPU mining is not very profitable with the low exchange rates at the moment.