When I press the start button the green light shows the computer powes on however the HD indicator light won't gon on and the computer would not boot. I have to keep the switch pressed for a few seconds to turn it off. After I repeat the procedure two or three times the computer finely boots.

Step One: Take out all the Cables.
Step Two: Take your PC and Goto the Roof or the Highest point you can find.
Step Three: Lift The PC as High as you can.
Step Four: Throw The PC down with as much Force as can.
Step Six: Take Pictures and Post em here.
Step Seven: Don't do any of the steps mentioned above if you value your PC And Follow the link below.

http://www.daniweb.com/forums/post1240349.html#post1240349

Well? any progress?

I haven't tried yet, I will let ou know as soon as I try

Today it booted on the second try

It could be overheating. But can't say for sure.

Remove the battery or re-set the CMOS jumper to clear the CMOS. resart and boot into DOS mode (F8) to see it you have any drivers that hang when starting.