Bitfury’s 400GH/s Bitcoin mining rig uses 16 individual hashing boards controlled by a single Raspberry Pi
BItfury ASIC chips use a 55nm process and are sold running at an estimated 1.56 GH/s per chip, with demonstrated performance up to 2.7 GH/s. Although they are clocked slower than Butterfly Lab’s 4 GH/s chips, they will run 4x more efficiently at 0.8 Watts/Ghps. Power efficiency will be a deciding factor in a bitcoin miner’s longevity as profitability narrows with increasing difficulty.
Building this project will allow you to use a Raspberry Pi as a 'headless' controller and status monitor for your USB bitcoin mining devices. The project incorporates an LCD to display hashrate, error rate, share data, network difficulty, mining duration, & current exchange rates.