White lines at the top 3-4 inches of the screen.

what is the cause for the televisions screen to get white spots that spread

You have some bad capacitors. They are located very near and next to your vertical IC. I would guess you would have to replace maybe four of these! Thanks for asking!

It sounds as though you can see Transmission lines which are sent out with any broadcast at the top of an image, The TV should normally blank these out, i suggest checking your horizontal and vertical settings

Check for open capacitors in vertical output circuit I believe 47 uf.

Yes you are correct. I would say 95% of the time, you will need a LCD screen replacement. Also be sure to disconnect and reconnect the lcd cables, at the motherboard and behind the lcd itself, just to make sure the cables aren't making bad connection.
I have provided you a link to MANY lcd screen for your laptop on EBAY.

http://computers.search.ebay.com/Satellite-P100_Screens-LCD-Panels_W0QQcatrefZC6QQcoactionZcompareQQcoentrypageZsearchQQcopagenumZ1QQdfspZ32QQfromZR2QQfsooZ2QQfsopZ32QQftrtZ1QQftrvZ1QQsabfmtsZ1QQsacatZ31569QQsargnZQ2d1QQsaslcZ2QQsbrftogZ1QQsofocusZbs

Hope this helps you. Please rate my solution.

Hello,

The white line is result of a Vertical failure. Believe it or not, the whole picture is contained in that one white line, but it is not spread out from top to bottom on the screen.

Usually, a vertical failure is IC or capacitor related. Should be an easy, fairly inexpensive fix for a competent repair shop.

Hope this helps you...

lcd or plasma.
are the lines solid or blurred. do they have sharp edges.
You may have a memory problem with the display which can only be repaired by factory trained technicians, or a brave soul willing to find parts on ebay.

Replaced C407 100uf/35V Vertical section.

YOU NEED CHECK THE 3 CRYSTALS ( RED, GREEN AND BLUE). CLEAN IT WHIT "DUST REMOVER" ( compressed gas duster) AND REPLACE THE COLOR WHEEL.

this symptom is what we called vertical fold-over. vertical fold-over is characterised by a white horizontal bar on the bottom or top of the raster due to the concentration or compression of the trace lines. it an image is present, the bottom or top portion is fold over. this is caused by a vertical deflection current with poor linearity, which compresses the trace lines at the bottom or top of the screen. this symptom is is caused by a defective sawtooth wave genetator circuit, or improper biasing or defective feedback circuit of the vertical drive or vertical output transistor/ic. the negative feedback circuit in vertical deflection circuit compensates for the linearity of the trace portion of the sawtooth wave. a decrease in the capacitance of the sawtooth generator capacitor is usually the trouble. but if you do not understand anything what i have written here, better bring it to a qualified tv technician for your own safety also. good luck!