Hi there
sorry to hear you are having problems with your ASUS netbook.
We shall start with elimination, try to connect an external monitor such as you use with a desktop PC to the blue video socket on the sides or back. It may not have a socket which should look like this
If you see a picture on the external monitor it proves the graphics or video card in the netbook is ok.
Look on the F buttons at the top of the keyboard and try to see if thiere is a CRT/LCD button, maybe a blue icon like this
It may not be the F8 key but have a look for a similar icon to this below
On this one it is the F7 button.
Press the fn or function key first. Hold this down as you press the F key. so it changes it's function.
Check your user manual if you are not sure on this.
Keep pressing the F key as see if you get external monitor or netbook monitor or both.
If the netbook monitor does still not show anything then look very close at the screen while you hold it an an angle and start it up
Look for very very dark images like when it normally starts up. If you can see feint very dark icons the netbooks screen backlight has failed and will need replacing. It may not be cost/effective.
If you can still see nothing at all on the screen it is either
1. screen inverter
2. graphics or video chip onboard the main board
3. a different main board fail
If this netbook was cheap it may not be worth repairing.
If you do want it repaired take it too a local guy if you can as you get better service.
All the best now, Phil