Welcome to the forum.
Have you installed the ASMedia SATA3 Driver ver:1.3.1 (or 1.3.8 for win8)?
You provided minimal information in your PC Specs.
You might need to flash to a newer bios version, for example, one fix in version 2.10 is Modify ASMedia SATA3 can't detect HDD when CSM disable.
Check out ASRock > Z77 Extreme4 (show all downloads)