Acer cmos boot problem

Hi

I been having problems booting with my acer extensa 5220. Can only get it to turn on when i remove the cmos battery. if i remove it then put it back in i will be able to switch it on. however as soon as i cut the power, it wont turn on again until i remove the battery and reinsert it. I have tried removing all the components except the CPU but still get the same problem. have checked the power jack ac adapter and cmos battery with a multi meter and they are all fine. when i put the charger in the laptop will just stay on a flashing amber charge light, i do know the battery is virtually dead but also know the laptop will run strait off the ac adapter. there should be a green light to tell me the board is ready to turn on but when i take out the battery and just use the charger there is no lights unless i take out the cmos battery and reinsert it. appreciate anything you guys can think of.

 

Have you got any kind of overclocking software setup on this pc.??? ed

 

No it will do the exact same thing without a hard drive. is it safe to run it without the battery because as far as i know that only stores configured settings and the date/time or can it damage the board?

 

It will not damage the board, and as long as the pc has power it wont know the battery is gone. Till the power go's off. ed