Intel Motherboard — warranty issues

Address:

Ratnagiri, Maharashtra

hello,
this is Dr. Aniket Pujari.. i upgraded my computer from a local hardware dealer who happens to be quite well renowned in the city. but very soon within 2 months the motherboard started giving problems.after complaining several times he tried to repair it. it functioned but not like a new one.now again its not working.i am half way thru the warranty period.but i dont trust the dealer. he might be repairing it himself n claims he sent it to the company. this has happened almost 5 times now. kindly help. how can i contact the company ppl to verify its originality. thank you...