I have a Samsung 64D7000. The original panel was replaced because of a peeling screen filter. This new panel has a screen uniformity problem that I described in the thread entitled "Green Blob back again for 2013!" I did not supply a link because the thread, even though it is not apparent by its title, is for Panasonic ST60 models. However, in that thread, before I realized its purpose, I did describe the problem and quote it here:
...on my panel there is a smooth pink relatively narrow vertical amorphous area on the left. Moving to the right, there is a wide vertical amorphous greenish area followed by a narrow pink one followed by a wide greenish one followed by a very prominent pink area. The areas are almost from top to bottom on the screen.
It is not caused by sub-pixel not firing. It is very similar to what I had on my Panasonic px80u. It is very annoying while watching B/W movies -- with the color control at zero.
In addition, the uniformity problem is a function of screen content. When a full screen gray or white pattern is displayed, the issue is very evident. However, if a black box of about 20% (or greater) is inserted anywhere on the screen, the uniformity improves and the problem is barely visible. That makes it not very intrusive, if at all, when viewing normal content. It is more annoying with black and white content especially with low APL.
Today I checked the Vs and Va voltages on the power supply and found them almost exactly as specified by the sticker on the panel. Vs was 217.3 (sticker is 217) and Va was 55.8 (sticker is 55.) Increasing these to 219 and 57 respectively seems to improve the situation -- but far from enough.
I did increase and decrease both voltages for the available range of the control for a few minutes and saw no improvement -- some slight change but no real improvement.
Any help would be appreciated.