Why My laptop is not charge and dead screen

Hi @tuyenhoangvan

If you have a DMM (digital multimeter) check if there's 19.5V DC getting to the motherboard when the charge is connected.

If not there may be a problem with the DC-In jack (supplier example only).

What can sometimes happen is that the centre pin of the jack breaks internally and this opens the +ve input supply lead from the adapter so that the motherboard doesn't receive any power to operate e.g. no charging, no display.

If the jack is faulty it cannot be repaired it has to be replaced. search online for Dell Vostro 5415 DC-In jack to find suppliers that suit you best.

Here's the owner manual for the laptop that may help. Go to p.50 to view the pre-requisite steps and then the procedure to remove/replace the DC-In jack (aka Power adapter port)

Initially you don't have to remove it, just disconnect the jack cable from the motherboard and check if there's 19.5V DC between the pins when the charger is inserted into the port.

Once you have power on the motherboard then you can move on to find out why the screen doesn't work unless the two problems i.e. not charging and dead screen were related.