I replaced mine about a month ago... so far so good. The original chip lasted about 4 years 3 months (3 months past my Best Buy warranty...go figure). I have read many posts from frustraited owners...some with sets a little more than a year old....all the way to 4-5 years. I hope I can get at least another 4 out of this chip. I imagine the only folks with the answer to your question are TI (Texas Instruments)...they are the ones who make that chip. Perhaps they have made inprovements to the chip?
If anyone has replaced the White Dot Problem Chip on their Samsung HDTV, how long has it been, and is the replacement chip identical to the original, in the sense that it will again be faulty with the same amount of use?