Samsung 204b - random yellow square ?

[hellomcfly]

i have been using this samsung 204b for sometime now and it has been great, but recently i have noticed in the upper right hand corner, a small area is yellow/green , about the size and location of the X and max/min button when a fullscreen browswer or application is open.

i tryed new drivers , re-seating my video card, switch to the other dvi port

any other ideas ? or does it sound like i may need to take it back under extended warrenty ?