Dell Laptop screen issue, displays nothing
You can try removing the battery and that run your laptop on AC power only. See if that works.
Sometimes the memory slots goes bad, so what you can do, remove one stick of RAM , see if it works, remove the other and put back this and check.
Also you can try below.
1) Switch ON your computer, start pressing the "F8" key continuously to get "Windows Advanced Options"
2) Select the option "Last Known Good Configuration".