Bitcoin mining difficulty is a competitive effort. An “arms race” was noted through the multiple hazing techniques used to mine bitcoins: fundamental CPUs, high-end GPUs prevalent to many gaming computers, FPGAs and ASICs were all used, each decreasing the profitability of less-specialized technology. Bitcoin-specific ASICs are now the primary method of bitcoin mining and have exceeded the speed of GPU by as much as 300 fold. The difficulty in the mining method includes self-adjustment to the accumulated mining power of the network. As bitcoins have become more hard to mine, the sales of high-end ASIC pr have increased in computer hardware manufacturing businesses.