Hi..I have been given this Laptop by my brother,it was functioning correctly and Battery Charging ,until,I tried to Power it on today as normal with the Battery and Mains charger installed and it wouldn't power up,absolutely dead! But as soon as I removed the Battery[Dell Type J1KND 11.1V Cap 48W],the Laptop would power up from Mains OK.Does this indicate that the Battery is faulty?is there any way to test it?or is there some other fault with Motherboard etc? any help appreciated Michael >NB I have tried discharging the circuits by depressing Power Switch for 20 seconds before installing battery and mains adapter but this doesn't make any difference.