On November 27, the United States Patent and Trademark Office awarded a patent to microprocessor producer Intel for a processor that can conduct "energy-efficient high performance bitcoin mining."
Specifically targeting the SHA-256 algorithm used in bitcoin mining, the patent argues that the proposed processor solves the energy consumption problem presented by current mining machines' reliance on hardware accelerators, such as application-specific integrated circuits (ASICs). ASICs typically process hash operations, such as the production and manipulation of nonces, in redundant multiple stages.
The patent claims that this redundancy could be curtailed through proper chip design. It explains:
"Dedicated Bitcoin mining ASICs are used to implement multiple SHA-256 engines that may deliver a performance of thousands of hashes per second while consuming power of greater than 200 W. Embodiments of the present disclosure employ micro-architectural optimizations including selective hardwiring certain parameters in Bitcoin mining computation. The hardwiring of these parameters eliminate the need for recursive rounds of computations of these parameters and reduce the overall circuit area and power consumption by about 15%."
A nonce is a random number only used once and is a key component of cryptography. As successful hashes must meet certain requirements to be approved, and as the data to be encrypted cannot change, a new nonce must be produced per each attempt – hence, the repetition and the power drain.
The patent also suggests that by changing how the nonce and the final hash are compared for validity, power consumption can be further lowered.