turn on display in lenovo laptop

[Sairam_1]

recently when i am pressing the on /off button in lenovo laptop display is not coming and the remainingwork regularly.you may say f9 but i had also tried it.I want a better possible way to encounter this problem

 

[Phillip Corcoran]

You press the Fn key first, hold it down, then press the appropriate F key (appropriate F key should have a screen icon it).