Asus India — laptop x505za

I bought a laptop from amazon on the 31st of august, and it has trouble opening. The screen remains black for 10 minutes and the majority of times it doesn't open until i restart it multiple times. Even in general when it opens it takes ages to get to the home screen. The overall performance seems to be exceedingly slow. I read some suggestions online which said to press the fn+f2 key to resolve it. But even it doesn't seem to work 9/10 times