hello, My sony vaio model SVF152A1WW screen turns to black/ it doesn't show anything when I hit the power button. It doesn't show any startup window or loading window on my screen. but the power led is glowing and the cooler fan is working as it is. I bought this laptop about a year and this is the first time i'm getting this issue and it really makes me feel bad. can you help me to solve this issue please.