BLack bar about 3" high near bottom of screen.

61" Samsung DLP. model HL-T6187SA. Service tech told the original owner that the problem is with the DMD board. WHile I can't troubleshoot, i can change parts and am thinking about trying to find that board somewhere and change it. My question is: do any of you know if the DMD board would likely be the culprit for there being a black band onscreen? Attached is a pic of the issue. The tech said the part is $230 but if I do it myself I first have to figure out where to buy the part.