I have a yellow bar on the bottom of the screen with a splotch of white.

It sounds like you may have an issue with the backlight of your TV. If a backlight is not getting adequate power, it can cause the screen to appear blue or have "flashing white splotches". The best way to resolve this issue is to have a qualified technician inspect the TV to determine if there are any issues with the backlight power supply. If there is an issue with the power supply, they will be able to replace it and resolve the issue.

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https://elektrotricks.blogspot.com/
https://electronicshelponline.blogspot.com/
Faults & possible causes to LCD screen are given with illustrations. You can get an idea about the fault to an extent. Search the site by type in the Brand Name of your set, in its search bar at the right side column, and press enter. See it in Webview with mobile or by desktop. Mobile View has no search box.

Fulvous Whistling Duck

With a new LCD screen, yes. Depending upon the age of your machine, and the cost of the screen, a new laptop may be more cost effective.

bad main digital board. It's the bottom board on the left, try Encompas Parts to get digital board.

If the splotches are a shawdowy black and look like mold growing between the Lens, its most likely dirt or water spots on the bottom of the large mirror. I cleaned mine and missed a few water spots on the bottom of the large mirror and the splotches (spots) showed on the screen. Other than Dirt, or water spots, There is nothing else that I can think of that would cause this. Unless the Someone has cleaned the screen and it soaked up between the lenes. But it Takes about 30 minutes to disassemnble, give it a good cleaning and put it back together.

Optics bad. Expensive > $1000 .

did you try change the VGA cable? if not, try it.

horizontal lines can be caused by either a faulty grapchics card or a faulty monitor. try adjusting the screen refresh rate. if you are using a windows xp system goto

start>control panel>display>settings>advanced>monitor

then adjust the screen refresh rate and see if the horizontal lines disappear. if not, then you probably have a faulty graphics card or monitor.