As a Certified Dell LCD engineer in Houston,Tx - Your problem is almost unmistakenly what is known as a defective tab. On the laptop there are 10-12 "data" tabs located on the top of the lcd which communicate vertical information from the board to the glass and 3-4 "scan" tabs located on the side that switch on which horizontal line to activate. These fail mainly to heat - but in some cases heavy shock or tension will cause intermittant problems. Repair to such a problem is EXTREMELY difficult and requires expensive machinery and skilled technicians. BUT - for those do it your selfers out there ill give you my advice. Go grab a moderately powered microscope, some acetone, tweezers, and your choice of liquor (your ganna need it for the shaking), and a very thin adhesive (like the stuff you use for your rear view mirror - the kind with the resin and activator) and a heat gun. Now go ahead and disassemble your screen down to the glass and board, find the tab which is damaged and remove it from the glass with the heat gun, remove all remaining adhesive with the acetone, using the microscope- youll find that both the glass and the tab have a +IIIIIIIIIIIIIIIII+ pattern on it. Line up the "plus" signs EXACTLY- place the resin on the glass, activator on the tab and press them togeather lining up the plus signs. Hold for about 2 mins. This CAN work if done right, but if you screw up it may be impossible to recover- Its worth a try and can save you about $100. Have fun