When i turn on the computer, the monitor stays blank, but it blinks.What should I do?

I checked everything, the connections and all, made sure they're all okay. But it still doesn't work. I tried restarting the so-called Batteries but still not. I've read that maybe it's about the VGA Card. But I know, if it's broken or damage, the fans wont start, right? But both the system unit fan and the VGA Card fan work. Please help me. Any suggestions?