However, unless you’re reading a crypto mining article from the early 2010s, you likely won’t come across the mention of CPU mining in regards to Bitcoin. However, there are some downsides to ASIC miners that have prevented them from dominating the entire crypto mining sector.ASIC miners are expensive, with prices typically ranging from $2,000-15,000 USD. There are numerous coins that are popular to mine with GPUs, with ether (ETH) being one of the most popular as of 2021. However, with Ethereum’s move to Proof of Stake (PoS), these miners may have to look elsewhere for profitable GPU mining rewards. Thus, even if a SHA-256 miner could theoretically be used to mine coins that rely on other algorithms, it is usually most cost-effectively deployed in mining a a cryptocurrency that relies on the SHA-256 algorithm – such as BTC of bitcoin cash (BCH). In addition, even the volatility of the cryptocurrency market itself can affect crypto mining profitability, as these mined coins can fluctuate substantially in price, thus affecting the profitability models of costly ASIC rigs and warehouses. Depending on the FPGA miner and the coin it’s mining, performance can vary widely, ranging from several 100 kh/s to over 20 gigahashes a second (gh/s), with a gigahash equalling a billion hashes.
For example, an ASIC miner optimized for mining bitcoin is optimized for the SHA-256 algorithm Bitcoin uses. At least one ASIC miner optimized for Ethereum’s ethash mining algorithm is already on the market, with ethash ASIC miners from other manufacturers scheduled for 2021 releases. Most of the best CPUs achieve 8-20 kh/s, and only a few (as of 2021) exceed the 20 kh/s threshold. This was possible because there were very few miners at the time, and the overall hash rate was therefore much lower when the Bitcoin network was in its infancy. Miners also tend to look at how much electricity a mining rig uses, including both its overall energy consumption and its efficiency in terms of hashes per kilowatt-hour. While mining rigs have various technical features, crypto miners are generally concerned with two above all else: hash rate and energy usage. Cryptocurrency miners are used on all blockchains that utilize Proof of Work (PoW), which is the consensus mechanism used to securely process, verify, and confirm transactions while hindering double-spending and other blockchain attacks. That said, CPU mining is a thing of the past for mining BTC and many large-cap PoW blockchains. The rising hash rates of Bitcoin and other popular PoW blockchain projects is just another sign of how sought-after crypto mining rigs have become.
As a result of this cycle, most miners of most large-cap cryptocurrencies have moved on from CPUs and started using graphics processing units (GPUs) to mine cryptocurrency, as these systems tend to be more efficient for mining and have a much better hash rate than CPUs. This allows you to mine cryptocurrencies indirectly without exposing yourself to as many of the sunk costs and maintenance requirements of specialized mining hardware. One thing to be vigilant about when trying to cloud mine is to choose a reputable provider. Much like you can meet your data storage needs by purchasing cloud storage, you can purchase a cloud mining service or contract from a cloud mining provider. While some crypto mining rigs are purpose-built, general-purpose mining rigs (very much like your own computer) can also enable you to take part in mining cryptocurrencies. Further, some projects, such as Monero and Ravencoin, are deliberately structured to remain ASIC-resistant (meaning that using any ASIC device is generally not cost-effective). In fact, a large number of ASIC mining operations must be executed at scale to be competitive – with warehouses that may be filled with hundreds or thousands of ASICs.
The primary rationale behind this design decision is to allow ordinary retail miners to be able to profitably compete with the large-scale institutional miners that have come to dominate mining on other major blockchains. This type of specificity is part of why some blockchain projects are still dominated by GPU miners. While CPU hash rates are measured in kh/s, GPU hash rates are measured in megahashes per second (mh/s), with 1,000 kilohashes equal to one megahash (a million hashes). FPGA miners are called “field-programmable” because they can be programmed or changed “in the field” after they have been delivered to a customer’s preferred destination. You can typically purchase cloud mining contracts that vary by duration (anywhere from weeks to years) and hash rate. CPU chip mining is measured in kilohashes per second (kh/s), with a kh equaling 1,000 hashes. The hash rate is measured in hashes per second (h/s), and is related to the likelihood of solving the cryptographic puzzle necessary to receive the block or mining reward.