I've got a 5-year-old Studio 1558 which lived through a lot (replaced LCD panel, keyboard, touchpad, HDD, the case has its wear as well), but recently a new strange defect on the LCD panel appeared.
It is an LG-manufactured (the technician who replaced the previous one showed me that) 1920x1080 panel. The laptop's GPU is Radeon 5470.
The problem is, a vertical stripe on the left side of the screen (I measured it to be exactly 240 pixels wide) shows the image a bit brighter than the rest, here's an image: Image may be NSFW.
Clik here to view.
I am 100% sure it is not a software issue, as it persists when I switch resolutions (it affects the same physical pixels) and even in the BIOS setup.
Now, the weirdest part is that it doesn't seem to affect the black or white point of the image at all. Instead, it seems that the gamma curve is slightly off. I'm not sure which one is correct (in the sense of being closer to sRGB or "how it looked before") - the stripe or the rest of the screen. But in fact if I open something like GIMP, open any image (or create some test one with gradients), select a portion that lines up with the defective stripe, open Levels and apply gamma of about 0.93 in the red channel and 0.95 in green and blue channels, the difference becomes almost imperceptible.
Now, I know that the laptop is long after its warranty period and it can actually do anything because of its age. But what might it be? And is it something that can be fixed by replacing some internal cable or, well, anything other than replacing the whole panel, which is otherwise fine (no dead pixels or anything)?
