how to fix not working keys? (especially f3)

[KPopper16]

Hi! Everyone

My laptop doesn't have its own lcd screen anymore (It just didn't show anything at all) and i already take it off. So, we used an external monitor to see. For the monitor to work, we need to press Fn+F3 (F3=Monitor).
But, there is a time when i opened my laptop and press Fn+F3, nothing showed up. Addition to that, when i open my laptop, a bit long beeping sound is coming out off the laptop's speakers.
First, i tried to use the monitor to other notebook, and it worked just fine. Second, i bought a standard keyboard, without the fn, i thought that the f3 is the problem. But, when i connected the keyboard (USB keyboard) i tried to press FN (from the laptop) and F3 (from the standard keyboard), and nothing appeared from the monitor. I tried to disable the function key by pressing FN+Num Lock or FN+Scroll lock but nothing happened. I also tried to use the function key to other keys (*FN+F4=hibernate) and it worked. I don't know why? Maybe the f3 is not working or the fn!
I hope you can help me fix my problem or is there a desktop keyboard with function keys!!!

Laptop Version: Samsung Sens 710
RAM: 256MB
Intel Pentium III Processor
710+ mHz
OS: Windows XP SP2

Thank you all!!!

 

[Phillip Corcoran]

The only sensible & worthwhile fix is to have a new screen fitted to the laptop, plus fix any other problems that become apparent (if any).