Is it possible if you purchased a bitcoin miner such as an antminer that cracks sha256 and edit the software so it could just crack normal sha256 hashes such as that you could use it with things like johntheripper or hashcat? I know us over in the hash cracking community would love to see such a great improvement in speed even if it's only for one specific hash type.
A bit of googleing landed me here: https://rya.nc/asic-cracking.html
Basically he says there are two main differences between mining and cracking.
- knowing when your done
- moving onto the next try
If just one of these things are implemented in the hardware, then there wont be much of a performance gain. But if they're both implemented in the firmware, you could potentially re-write it to suit your needs. So you'd really have to ask the manufacturer of the hardware.