The LCD screen on my Toshiba TE 2100 flickers non stop

The LCD screen on my Toshiba TE 2100 flickers non stop. When I connect to an external monitor, I don’t have such problem.
I’ve called a few guys and each offers me different opinions. Some told me that the graphic card is the culprit, some pin point the LCD screen. Others suggest the problem could be due to the inverter, yet some suggest that it could be some chips on the LCD screen that required replacement. After getting all these preliminary advice, I ended up more confuse. Therefore, hope that you are able to tell me the cause of the flickering LCD and ways to rectify it.

I would say that everyone who gave you an advice is right in some degree. The problem might be caused by a failing video card, the video cable, the FL inverter board, the LCD screen or just by a loose connection. It depends on how your screen flickers. You can find some video troubleshooting tips here. Here are my thoughts.
If the screen looses the backlight intermittently but you still can see some data on the screen, them most likely the FL inverter board is the culprit and the problem could be fixed by replacing the inverter.
If the screen flickers and losses the data (any image) but the backlight stays on all the time, then it is possible that the video cable is bad itself or the connection is loose.
If the screen flickers without loosing data and the backlight then it is possible that the screen or the video card is going bad. First of all, I would try to reseat all connectors related to the video output. If you give me a better description on how your screen flickers, I might have a better advice.

Here is Toshiba TE2100 laptop disassembly guide.