Laptop not booting after update

Hi guys I'm having trouble with my laptop which is an Asus X52f
It was working fine up to a few hours ago then windows update told me to restart to install new updates so I did. Now every time I press the start button it lights up and the Asus logo appears on the screen but after that nothing but the led light shows with a flashing horizontal line on the top left side of the screen ....I've searched a lot online and many people recommend un plucking it, removing the battery, holding the power button for a minute and plugging it again and start it.....I've tried this but the same thing as described above happens every time I turn it on, I also opened the back dusted it removed the ram and tried it without any ram, with one stick and with both yet the same thing happens ...id like to add that when adding one ram stick or no ram at all, the back light doesn't go on but the fan works whereas with both ram sticks the back light goes on but the fan doesn't start

Can anyone please help me?
Many thanks