My Asus x550 will not boot. HD lights for a second, fan starts and nothing. HDD and battery are internal.

[lee75757]

ASUS tech support walked me through reset by holding power on for 45 secs/ Before that it would boot but would randomly reboot. Now HDD on lights for a second then nothing.

 

[fagetti]

does it restart itself or just keep going with fan on? what happened before this