Unfortunately, Express Gate does not support installation on HDD in AHCI or RAID mode. When you install Express Gate on HDD, please note the following conditions:
1. ASUS Express Gate supports installation on SATA HDDs in IDE mode or SATA mode only.
2. ASUS Express Gate supports SATA HDDs connected to motherboard chipset-controlled onboard SATA ports only.
Note: ASUS Express Gate supports installation on USB HDDs and Flash drives, but the software performance might be a little bit slower than that on SATA HDDs .