I was attempting to fix my father's Samsung 55"" TV. This was the exact replacement part for the power board. The symptom was that sometimes the TV would power on, sometimes it wouldn't. If it wouldn't power on, the only way to make it work was to pull the plug, then plug it back in, and then it would turn on. That, or attempt like 10-20 times on the remote until it finally came on. The red power light was illuminated anytime the TV was off. We did a lot of research and read a ton of customer reviews and it all pointed to this power board. However, it actually ended up being the main board that needed to be replaced. So, keep that in mind if you have the symptoms I described on your TV.