Cmos configuration not available by pressing del...

Question

my gigabyte mobo no longer operates normally. What I did is to configure first its cmos setting by pressing del upon loading but i can no longer be displayed.. Please do help me how to fix the problem..In other words no matter what i do it is no longer usable because i can no longer configure the cmos setting for its failure to display. the pc hangs after detecting the cd rom and hdd then stops,,, if i press del the cmos will not be displayed