t61 video card

hi, i found out my t61 video card is causing my lcd screen to not work...but if i connect to the external monitor it will work. but when it is at the xp loading page or at the bios menu, it will show like rain drop lines accorss the screen. and when it get into desktop, the lines are gone.
but a few times when i restart, the rain drop lines are gone and things can show on my internal lcd.
so i am not sure if it is the hardware problem of the video card, or maybe the driver or some software problem? plus when i install video card drivers, it will always black out during the process.
if it is the video card, how much do you guys think it will cost to replace it by lenovo or local store?? i am out of the warrenty. it is a 140m card.
thanks all.

 

It seems odd your notebook's screen won't work, but an external LCD does. It would seem more likely there's something wrong with the LCD. Is you machine under warranty?

 

your video driver should install with no problems. If it doesn't, then that's the problem.

there's a software called "driversweeper" that can search and wipe out old video driver files before the new one gets installed. Search it up, it may solve your problem.