Xu Sun, since you already tried different AC adapters you can most likely rule it out. I would first check the DC plug on your motherboard. Make sure it is properly connected and that it does get power. check the connectors was any broken solder.
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Xu Sun, since you already tried different AC adapters you can most likely rule it out. I would first check the DC plug on your motherboard. Make sure it is properly connected and that it does get power. Check the connectors for any broken solder etc. To work on your laptop, get the service manual [http://support.dell.com/support/edocs/systems/insM5010/en/sm/index.htm|from here.]
Xu Sun, since you already tried different AC adapters you can most likely rule it out. I would first check the DC plug on your motherboard. Make sure it is properly connected and that it does get power. check the connectors was any broken solder.