Intel
Oot problem

I purchased intel mother board (DG41RQI) and intel processor in august. now the problem is, PC is not booting (normal operation) while connected with hard disk, it is mention that no hard disk found.when i disconnect the hard disk and boot with cd drive it is booting. my hard disk was normal when connected with other PC and it is booting normal to other mother board. i dont know what is the problem. please tell me the details