Thanks For ur reply.
i'm having GA Z77X- UD3h mobo, I5 2320 CPU, 16gb Corsair ram, AMD 5670 1gb DDR 3 GPU, LG Bluray Writer, 250gb samsung SSD
Yosemeti is my current os, i installed like usually, loaded all defaults in mobo n changed the XMP to Profile 1.
normal clean installation n dsdt...