If you have a blackscreen when boot up and lights of battery, ac and wifi are on,just clear cmos battery. Does the other things not work? 20 sec powerbutton etc.. Step 1 remove batt and AC. then open your eee pc. for more details see: forum.eeeuser.com (only till step when you can see motherboard). (please be carefull! I am not responsible for your actions when it goes wrong) Step 2: Right below you will find a white plug which is connected with your cmos battery. Disconnect it from motherboard and wait 20 sec. and reconnect. To test it, please attach the battery and push start button to see if it reboots. Step 3: If it reboots the cmos battery is cleared, turn off eee pc and put everything back to place. And there you go…. it should work as before *Please note this blackscreen happens again. Do not use your eee pc on battery untill an empty battery! JUST MAKE SURE YOU TURN OFF YOUR EEE PC WHEN DONE! Hope this help you to work again with your handy laptop! Let me know when it works for you! Sorry for my English and uuhmmm…This video was taken in a rush, I was suprised it worked and I wanted to spread this to you all!! Greetings Indosolo
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EEE PC 900 HOW TO FIX BOOT UP PROBLEM : Clear cmos battery FIXED