It Is All About BTC, LTC, ETH, DOGE, KAS mining as well as other alternative crypto currencies
We’ve read some comments about people complaining from the stock ZeusMiner Blizzard Scrypt ASICs’ like them being crappy and getting too hot. From our personal experience we can also confirm that the 60W power adapters provided with the miners do get hot, but this is to be expected with a power draw of the device of about 44W at 300 MHz and 48W at 328 MHz. Our unit that we are currently testing is hot to the touch, but only using that to judge can be misleading as any temperature higher the one of our body is perceived as hot. Anyway, we did decide to try using the Blizzard miner with a high-quality ATX power supply and measure the actual power draw we are getting…
We have attached the ZeusMiner Blizzard to an 80Plus Platinum power supply and the result was a bit surprising – very low efficiency of the power supply due to the low load. Clearly the 1200W Corsair power supply is not designed to be very efficient with a load of just about 50W, actually 48-49W measured as used by the miner, so not much different than what we got from the standard PSU. The difference here however is that due to the low efficiency that the PSU is running at the actual power consumption of the miner off the power socket is about 64W. We did measure 48W of power usage with the stock power adapter supplied with the miner at the power socket, so it seems that these 60W power adapters are quite efficient in converting the 220V power to 12V. Of course by increasing the number of miners connected to the power supply and raising the load to at least 10% or more the efficiency should increase and make things right, though no point in running just a single Blizzard off an ATX computer power supply – better stick to the power adapter supplied with the miner.
We have been using and testing the 27 MHS GAWMiners Falcon Scrypt ASIC miner for a few days already and we did measure the power requirements of the device and are ready to do some recommendations for a suitable PSU to use. On the GAW website the power consumption of the miner is stated as 1040W and since this is essentially a ZeusMiner THUNDER X3 inside, we have also checked the specifications announced on the Zeus website – 920W. Zeus however does recommend a 1200W modular 80PLUS Gold or Platinum rated power supply to be used for this miner, though you can actually do well with a slightly less powerful model if it is a good one.
As you can see from our measurement on the image above, where we are using a Corsair 1200W 80Plus Platinum power supply, the actual power usage of the miner is 916W, so very close to what Zeus has stated on their website. The fact that we are using a more powerful 80Plus Platinum power supply gives us very high efficiency of over 94% at this serious load, so the total power consumed at the wall is roughly 970-975W. This means that even with a good quality 80Plus rated 1000W power supply you should be fine. No need to go for 1200W as recommended, though the higher power model will most likely help you minimize the power wasted as it will be operating at better efficiency when not pushed to the limit. We did a test with a 1000W power supply that was barely managing to work at 78-80% level of efficiency and got a power usage of almost 1100W at the power socket. So if you want to save yourself some heat and waste less power, you better go for at least 1000W power supply that is rated 80Plus Gold.
We have already published some interesting findings about the power usage of the new GeForce GTX 750 Ti graphics cards when used for crypto mining and recently we have built a 6-card GTX 750 Ti mining rig. We have taken some time to also measure the power usage of the individual cards as well as the total power usage of the whole system in order to give you some additional details about what you can expect in terms of power consumption from such a mining rig. We have used Gigabyte GeForce GTX 750 Ti video cards (N75TOC-2GI) that do have an external onboard PCI-E power connector and we started by measuring the total power that goes to a single video card both trough the PCI-E slot as well as through the external PCI-E power connector with the help of a watt meter that is attached directly to the power lines going to the video card (using a powered extender).
As you can see on the photo the total power used by the video card is about 31W (with the card running at +135 MHz for the GPU and + 610 MHz for the video memory). Note that this power measurement is on the 12V line from the PSU going to the video card, so it does not take into account the power efficiency of the power supply and as a result the total power used by the video card from the mains will be higher by something like 15-20% (depending on the PSU). Note that we have used a powered PCI-E extender with USB 3.0 cable for the data lanes. This extender takes all the power provided to the PCI-E slot of the video card through a 4-pin molex connector and supplies both the 12V and the 3.3V power that the card uses drawing only power from the 12V line (there is a voltage regulator to output 3.3V from the 12V input on the extender’s board). So what the wat tmeter shows is the total power going from the PSU to the video card and in the case of the Gigabyte GTX 750 Ti it was 31W. Again the total power usage from the mains will be higher as this measurement does not take into account the power efficiency when converting 220V/110V to 12V.
So what is the situation with the total power usage per GTX 750 Ti video card from the mains? The easiest way to check that is to measure using a watt meter connected between a power socket and the power supply of the computer the total power consumption of the system with 6 cards and then disconnect one card and to measure again. The difference we got using this method was about 79W, though this is not for the video card only as it also affects a bit the overall power consumption of the whole system. Also note that the measured 374 Watt for the 5-card and 453 Watts with the 6-card setup are with the video cards overclocked to +135 MHz/+610 MHz. The results we’ve got with the cards running at the stock frequency were 367W with 5-cards and 432W with 6 cards or a 65W difference per card (total power used from the mains). This difference of 14 watts between stock and overclocked frequencies brings roughly about 40 KHS more in terms of hashrate for Scrypt mining (per card). Have in mind that our power supply used had an efficiency rating of about 80-85%, so this means that 15-20% of the total power used at the mains is actually wasted in the conversion between 220V/110V and 12V.
Another interesting thing that we have noticed while testing the power usage and overclocking capabilities of the 6-card GeForce GTX 750 Ti mining rig was the total power consumption that we got for the system with the power target limit changed from the standard setting of 38.5W to the 65.5W. The watt meter showed an increase of power from the 453W with the 38.5W power target limit to 556W with the 65.5W power limit – about 100W increase with the same operating frequencies with a slight increase in performance of about 90 KHS total from the 6 cards or roughly a bit over 1W per KHS and in our opinion this is not worth the extra increase in power usage, so raising the power limit may not always be a good idea!