I have Dell Inspiron 15 5000 laptop bought  2yrs ago. Last week I connected the charger it beeped . 4 beep loud. I disconnected the charger. And switched on the laptop it beeped loud when desktop is came it beeped not so loud . Again I shut down and start it no beep sound.  And it was working normal . Today it started beeping 4 beeps I didn't connect the charger. Kindly help me.