All I know is, I want another 2TH ASAP, and not sure which horse to bet on; Coincraft or CoinTerra
Would love to buy more BitFury product (even though it's 55nm), or KNC, but neither appear to be available for purchase/delivery before the new year :/
*grumbles*
simple comparison of some coincraft and cointerra specs, some are chip related some are rig related...
1. chips - both fabbed at globalfoundries 28nm process. both anticipating silicon arrival in december
2. coincraft chip specs claim 0.65W/GH Cointerra claims 0.6W/GH/s. not much difference. both are claiming at 0,765volts for nominal speed (not surprising since both are the same process) and in theory both can be over or under clocked and over/under/volted in a similar way. at nominal 2 th/s just the chips would consume approx 1200-1300 watts, but with dc/dc converter inefficiencies, and controller, and power supply inefficiencies, and cooling systems assume both would consume around 1700-1800 watts for 2TH/s nominal.
3. coincraft claims use of single atx power supply at 1800 watts, cointerra claims use of twin 1100 watt psus. cointerra's psus will be in their most efficient operating range of 94% when running at nominal speed - i.e. not run at 100% load, coincraft will be in the psu's worst efficiency when running at full load. perhaps <87% efficiency. running cost over 1 year with 8% loss of efficiency is expensive (hundreds of dollars in electrical and cooling costs over a year)
4. household outlet load. some household outlets limit power output to 1500 watts. if trying to draw 1800 watts from one circuit, there's a chance it will be overloaded and trip breakers/fuses or worse. cointerra uses twin power outlets for its twin psus. irrevelent in a data centre where abundant power is available.
5. overclocking. coincraft running 2th nominal at max load for the supplied psu. extra psu will be needed for overclocking (add $300? plus some space for it in the rack). cointerra has extra margin of power for over clocking. (2200 total power available in box)
6. controller board. coincraft rig has raspberry pi. cointerra has beaglebone black. latter is more powerful. not sure if that makes a difference but 2 TH is a lot of hashing performance the controller has to keep busy. even a 550 gh/s kncminer uses a beaglebone black so bitmine may have underpowered the controller. tbd.
5. cooling. 1800 watts is a LOT of cooling requirement. cointerra is using liquid cooling, and coincraft is using air. thats asking a lot of their fans and heatsinks to cool that much heat, so we will see if it works.
6. january price for 2 TH, coincraft is $12,000, cointerra is $6,000
hope that helps