frozen on apple logo

i have an ipod classic 160 gb and a week ago it froze so i reset it , but it then just froze on the apple icon. tried resetting it numerous times, over the past week ive charged it,let the battery drain, recharged it , all the while trying to reset and failing. its not showing up on my computor or in itunes and just remains frozen on the apple logo. could anyone please give me some advice ?