Probably one of the pulse xformers that drives the backlights. Buy a new monitor, they seem to be about what it would cost to repair it. https://www.samsung.com/us/business/computing/monitors/flat/27--led-monitor… Sent from my iPhone On Dec 3, 2023, at 13:44, Van Snyder via cctalk <cctalk(a)classiccmp.org> wrote: I have a formerly-gorgeous 27-inch Samsung monitor: Model LF27T350FHNXZA Serial 0AS1HCNR904588L S/W M-T3527FGGA-1006.1 that now has a minor defect. The "wallpaper" has a dim stripe about 1/6th of the screen width, top-to-bottom, about 1/6th from the right edge, where the blue band appears when I run its self test. Windows display almost normally, with a little bit of dimness in that band for some colors. White is fine, black is gray, .... Changing the wallpaper doesn't change it. Fiddling with its internal settings doesn't change it. Photo at http://vandykle.mynetgear.com/Samsung-27.jpg. Is this the sort of thing that can be repaired at reasonable cost, or should I just live with it until the monitor fails altogether?