White horizontal lines on startup that recede to the bottom of the screen.

[bozzle73]

When I got this used computer the first time I fired it up the monitor had white horizontal lines running about 1/2 way up the screen. As I sat there for about a minute, they slowly receded to the bottom of the screen and didn’t reappear. I wrote it off to a driver glitch or some piece of hardware getting settled in.

I turn a laptop completely off when I know I’m done using it for the day. I’ve noticed that this computer has the white horizontal lines if the computer is shut down for any length of time (longer than a few hours). The longer the computer is left off, the higher up the screen the white lines go when it’s turned back on. EDIT: This also happens when the computer is awakened from sleep mode.

When there's a large block of white on the screen I can't see or access anything behind it. None of my icons are visible where it is white, and nothing can be clicked on. The computer goes through its normal startup, and the lines just keep slowly receding until they hit the bottom of the screen, and the computer operates normally after that - for now. 

Here are images of what I see when I turn the computer on from Windows startup, the Welcome screen, and finally my desktop. It takes anywhere from 30 seconds to a minute for the white line to disappear, depending on how long the computer has been off. These were taken after it was off for 12 hours.

Does anyone have any ideas what may be causing this issue? Before I start tearing the monitor apart I’d like to know if it looks like the graphics card or something major is going bad. Aside from this issue the computer works like a champ.

[bozzle73]

Updated my original post with some pictures. Does anyone have any suggestions about what may be causing this?