The Commodore 64 is one of the most important computers in history, along with being the highest-selling single computer model ever. It was sold for almost 12 years, from August of 1982 to April of 1994, though it was extremely outdated by the time it was discontinued. The success and popularity of the Commodore 64 can be attributed to its affordability and performance. It had a MOS Technology 6510 8-bit processor running at just over 1MHz, 64KB of RAM, and a special VIC-II graphics chip, which were all quite impressive at the time. But that hardware is laughably slow today, which is why it is amusing to see a Commodore 64 being used for Bitcoin mining.
Bitcoin is the cryptocurrency — so much so that it is almost synonymous with cryptocurrency in general. Bitcoin is entirely digital and isn’t backed by hard currency, and there isn’t any central authority that keeps track of Bitcoin balances or transactions. Instead, each transaction is logged within the blockchain, which is a massive ledger shared by every Bitcoin user. Transactions, encoded as “hashes,” that are added to blockchain need to be verified mathematically by multiple independent entities, which is a computationally expensive process. The owners of computers that perform those verifications are compensated with a small amount of new Bitcoin — usually with a value slightly more than the cost of the electricity required to perform the computations. Bitcoin miners build computers specifically for the task in order to earn money.
If you have a vintage Commodore 64 sitting around collecting dust, it turns out that you can use it to mine Bitcoin. You can do that with the help of software developed by Maciej Witkowiak called C64 Bitcoin Miner. This software does the same thing as any other Bitcoin mining software: it processes transaction hashes. Specifically, it is able to work at a whopping 0.2 hashes per second. To put that into perspective, Bitcoin mining rigs today are often measured by how many gigahashes (billions of hashes) are processed per second. In addition to the ludicrous inefficiency of using a Commodore 64 for Bitcoin mining, you also have to contend with some practical challenges of retrocomputing. For example, the Commodore 64 did not have any built-in network adapters. So you’ll need some sort of serial link or external modem just to access the Bitcoin blockchain. Obviously, you should never run C64 Bitcoin Miner to make money; in reality, you would spend far more on electricity than you would make in Bitcoin. But it would be fun to show your crypto buddies your “new” mining rig.