I have motherboard H8SCM-F with Seagate hard drive model# ST1000NM0033 which is a SATA 3.0 (6.0GB/s) hard drive but the system indicates that the drive is operating at only SATA 2.0 speed.
The onboard AMD SP5100 controller is a SATA 2.0 that can support only up to 3.0GB/s. When a 6.0GB/s drive is installed, it can only be backward compatible with the onboard SATA controller, which is 3.0GB/s.