Ethereum Classic is a cryptocurrency that was created as a result of a fork in the Ethereum blockchain. It is identical to Ethereum in terms of functionality, but differs in terms of its blockchain history.
While Ethereum has moved on from the fork that led to the creation of Ethereum Classic, the latter still maintains the original blockchain.
As a result, Ethereum Classic is often seen as a more “true” version of Ethereum, and is mined in a similar way. However, because it is not as widely used or accepted as Ethereum, it can be more difficult to find places to mine it.
GPUs are typically used for mining cryptocurrencies, and 4 GB GPUs should be able to mine Ethereum Classic without any problems. However, because Ethereum Classic is not as popular as other cryptocurrencies, it may be difficult to find pools or solo mining opportunities.
Additionally, because it is not as widely used, there may be less demand for mining equipment that is specific to Ethereum Classic. In general, however, 4 GB GPUs should be able to mine Ethereum Classic without any issues.