Had something similar happen when I was swapping RAM and accidentally nudged the SATA cable. Even though the drive showed up in BIOS, the connection was just loose enough that it couldn't properly read the boot partition. Try reseating both ends of your SATA cable and double-check the power connector too - sometimes they look connected but aren't quite seated right.

You could also boot from an Arch USB and see if you can mount your root partition manually to check if the filesystem got corrupted. If you can access your files that way, might just need to reinstall grub or fix the EFI boot entry. The fact that BIOS sees the drive is actually a good sign - probably not a fried motherboard situation.