the hashboard reports asic 0, despite the RI signal is OK and the first chip has been replaced but the issue persists,
If the board is reporting 0 asic, despite the RI signal is OK and the first chip has been replaced but the issue persists, there are a few possible steps you can take:
4.1 If it report 1 asic.
Inspect U88 and the IO interface for any potential issues, such as loose connections or damaged components.
4.2 If it still report 0 asic.
Consider re-soldering the first chip, ensuring that all the pins are properly connected.