Safe as no erasure of your data is done. See it in the CNET Laptop Troubleshooting forum at link.
Be sure to unplug all USB things when you do this.
-> http://forums.cnet.com/7723-19681_102-352085/welcome-to-the-laptop-troubleshooting-forum-at-cnet/?tag=contentBody;threadListing
Bob
my dv4 1120us laptop is not coming on.i plugged in the original charger and there is no lights ,noise etc. i plugged in a different adapter and the led light in front ,next to the power light just keeps blinking.when i press the power on button it starts booting for at least 3 seconds an cuts back off....please help!

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