I'm not following, by hardware do you mean standard nodes or mining?
Hardware requirements required to host and replicate the entire Ethereum blockchain.
eg: It's possible to host a full Bitcoin node on a RasPi and USB drive. The Ethereum node software would laugh at a RasPi.
Extreme example, I know, but I've read Tweets from seasoned network techs who gave up trying to fully sync an Ethereum node on high-end servers.