GPU/CPU Mining: What to Mine in 2019 The Bitcoin mining market is competitive. Dedicated mining hardware has made it impossible for small-scale miners and hobbyists to compete with major mining pools, and with new ASIC units being developed and released on a monthly basis, the days of CPU or GPU mining — at least on the Bitcoin network — are over. Fortunately, Bitcoin isn’t the only cryptocurrency in the blockchain ecosystem. It’s still possible to mine hundreds of different cryptocurrencies with simple GPU rigs — in some cases, CPU mining is still viable. The most important question to ask, however, is whether or not GPU or CPU mining is still profitable. We’ll proceed to assess the current state of CPU and GPU mining and highlight the most promising alternative coins to mine without an ASIC unit in 2019 Is CPU Mining Still Relevant? CPU miners are now locked out of the Bitcoin mining ecosystem, but there are still many coins that can be mined via CPU alone. There are a number of factors that should be considered before CPU mining any coin, such as mining difficulty, price volatility, market capitalization, use cases, and developer background, but the blockchain ecosystem is home to hundreds of promising projects that rely on the efforts of exploratory, forward-leaning miners. The rise of the ASIC has also led to the creation of several efforts designed to thwart ASIC monopolization. The Cryptonight algorithm, for example, is designed to be mined inefficiently on ASICs, and is focused on establishing truly decentralized blockchains that can be mined by any network participant. Monero, Bytecoin, Electroneum, and DigitalNote are all examples of cryptocurrencies that operate on the Cryptonight algorithm. Ultimately, CPU mining altcoins in 2019 requires careful research and the ability to spot promising cryptocurrencies that deliver mining ROI — there’s no point CPU mining irrelevant altcoins that are destined to be cast into the deadcoin graveyard, but profitable options still exist. Monero Monero is one of the most popular cryptocurrencies that can be mined with via CPU or GPU. In mid-2018, the Monero network hash rate increased dramatically subsequent to the development and launch of cryptonight-friendly ASIC miners. A Monero hard fork in October 2017, however, swiftly eliminated ASIC participation in the Monero network. Monero has previously switched from cryptonight to cryptonight V7 in order to thwart the Antminer X3, but further solidified ASIC resistance by implementing cryptonight V8 — CN variant 2 and a number of other protocol changes. The “Beryllium Bullet” upgrade, or V8 Hardfork delivered a marginal increase in efficiency for Intel CPUs, but also included updates that bricked any existing cryptonight7 ASICs and made the production of cryptonight V8 ASICs prohibitively expensive. Overall, Monero is arguably the most cost-effective coin for CPU mining in Q1 2019. Bitcoin Gold Bitcoin Gold is a hard for of Bitcoin designed specifically for GPU mining. In order to promote a hash power shift away from large-scale ASIC farms, Bitcoin Gold shifted from the SHA-256 algorithm to Equihash, which favors GPU mining. Importantly, Bitcoin Gold has ignored recent bearish market action, maintaining a stable price point between $11 and $14 USD across Q4 2018 and Q1 2019. Horizen Horizen, like Monero, is a popular privacy-focused blockchain that allows users to send and receive transactions anonymously. Previously known as Zencash, Horizen is leverages the Equihash algorithm and is thus suitable for GPU mining. Notably, Horizen currently offers the highest level of reward amongst Equihash coins. Zcash Zcash mining currently takes up the largest portion of hash power directed at Equihash coins. Interestingly, Zcash mining is currently more profitable than Bitcoin or Ethereum mining, but does face a number of inflation issues. With a power consumption of just 100 watts with an average cost of $0.12 kWh, it’s possible to generate up to $85 monthly at current Zcash prices. If scaled in an efficient manner, Zcash can deliver a compelling ROI to GPU miners.