Read the following and decide if you're up to it.
http://simpletonpattern.blogspot.com/2009/09/how-i-fixed-my-dlp-tv.html
http://www.shopjimmy.com/samsung-4719-001981-dlp-chip.htm
Bob
Same sad story
Like everyone else, my 4 year old Samsung HLT5075SX/XAA began developing white spots in the upper left corner. Over the past 2 months, the number has grown to hundreds and the TV is no longer watchable. I noticed that the Samsung support on this forum has been helpful in resolving this same issue with other people. I called the 1800-SAMSUNG number and they said i would have to pay for a part to fix it. Is there anything you can do to help me out?
Thanks,
Shawn

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