I too have white dots on my Samsung DLP TV Model HL67A750 TV. You can get a service manual here http://www.tradebit.com/filedetail.php/133052760-samsung-hl61a750a1f-hl67a750a1f-dlp-tv-service-manual
You can buy the chip at Amazon here. http://www.amazon.com/Samsung-Mitsubishi-Toshiba-4719-001997-Chip/dp/B007JY58FM/ref=sr_1_fkmr0_1?s=electronics&ie=UTF8&qid=1363053477&sr=1-1-fkmr0&keywords=Dmd+chip+for+hl67a750 for $159.
This chip fits most DLP TVs.
I only have 4 dots now, but if it gets worse i will get the manual and the chip as I described above. Best of luck.
Here is an instruction video from ShopJimmy. It may save the price of the Service Manual. They sell the DLP Chip on Amazon that I mentioned Previously.
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