What coins can I mine with HDD?

The first and most important is the small number of available crypto coins. Today, you can mine Chia, Burst, Sia, Storj, and FileCoin on your hard drive.14 Eyl 2021

HDDcoin HODL Program HDDcoin HODL offers Coin Holders the opportunity to earn rewards on HDD locked in a Contract for specific hold durations .

Yes you can absolutely farm chia on an external hard drive . ‘Farming’ is just the mining equivalent for chia. However if you are not using an SSD as your temporary storage drive and doing it on a hard drive your plotting process will be quite slow.