Monitor keeps on turning off while working and blinking

Hi!
I just bought a new monitor – Asus PB287Q.everything is working well except that it keeps on turning off while doing important duties in my desktop. What usually happens is that it will turn off automatically. I will push again the power button and it will turn on. This will happen again after few minutes and for few times. I want to know what are the major causes of this problem. Is it my video card or my monitor itself? Can still fix this myself or do I need to bring it back? Can you show me how to fix this myself?
Thank you very much!
