Possible causes
- SATA cable not connected fully or properly
- SATA interface disabled in BIOS
- SATA cable bad
- SATA connector on motherboard broken, bent, or faulty (sounds like you eliminated this)
- SATA connector on drive dirty, broken, bent, or faulty
- Motherboard bad. Try different system.
- Drive not getting enough power, try different power supply
- If jumpers are on the drive, it may be in some weird diagnostic mode. Remove any jumpers.
- Short on PCB
- PCB damaged due to power surge, bad firmware update, bad NAND or NVRAM, or physical/liquid damage
- BIOS doing something it doesn't like on power up. Try connecting drive to system after BIOS completes POST and see if you can view it with a boot disk or utility that rescans buses. Alternatively put it in an enclosure or connect to another system. Update BIOS is this is the issue.
- Drive may be performing ATA SECURITY ERASE command. Leave connected to PC for 24 hours and then reboot and see if it comes back.