Why is my screen blank

A blank, blinking screen on an HP 700 laptop usually points to a display, RAM, or power-related issue. First, perform a hard reset: disconnect the charger, remove the battery (if removable), hold the power button for 20 seconds, then reconnect and try booting. Check RAM sticks - remove, clean the contacts, and reseat them firmly. Connect the laptop to an external monitor to confirm if the issue is with the internal display. If the external display works, the problem may be with the screen, cable, or GPU. Also, try booting with one RAM stick at a time. If all fails, seek professional diagnosis.

Here are the reasons. Fix these issues.

Pc's display cable is loose or damage

Graphics card issue

BIOS not booting properly

@kelvinmacharia ,

You say "blinking" what is blinking? Do you mean the LEDs are flashing? It may also Beep at you in patterns... If so, they are error codes and you can look them up on the following link (HP Support).

Click the (+) plus sign in a circle in front of "Identify the notebook light or beep code" look at the codes for one OR more that match what you're seeing...

...again click the (+) by those and read the meaning and actions you can take.

Follow the instructions that match your error code(s).

If, after you do that (or if blinking DOESN'T mean the LEDs) it still has a problem, come back and tell us what you found, what you tried already and what IS blinking, a video and photos can be helpful. And someone will be able to guide you better...

Good Luck!