Yoga screen problems

[millettedeborah]

Hi,
I have a lenovo 720 yoga that's less than a year old, that wont boot up, when you turn on fan? Starts for a sec then stops..and go's to a grey screen.
This has happened 1 time before, when 'puter was 5mo. Old. Took out battery and that worked. Now 4 mo.later same thing but this time taking battery out does not work. Help!!

 

[Reynod]

Hold down the power button for 30 seconds .. .when it reboots use the switch for safe mode to reboot it