MacBook Air 13" won't boot up
I press the power button, the boot sounds, white screen with apple logo shows up, process bar moves and the "wait" symbol turns around. However, when the process bar moves to about 15%, it disappear. And then computer turns down. It won't boot to OS. I press the power button and the Mac goes the same loop.
MacBook Air 13"
CPU: Core 2 Duo 1.86 GHz
Flash: 128 GB
What I have tired:
1. I tired SMC for few times, but it did not work out.
2. ⌘-⌥-P-R to reset, but it did not work out.
Can anyone help me to find the root cause of this issue? What else I can do to fix it? thank you!