8 beeps sound in dell n5010

Hi Sir,

am ravi kiran, My Dell N5010 laptop is having problem 8 beep sound.

am solved in service centers 5 times now
1st time it works 6months
2nd time 4months
3, 4, 5 it works 1 or 2 days only...

That Person told me Problem Repeats its not solved,

Solution totally replace mother board-- its n't beeter to me.

Please Give me Solution.......... Sir