I just inherited a problem child.. a Samsung 50" dlp hln5065w tv! Yeah... however... it runs for 2 hours then the colors start freaking out! first everything turns one color then it starts to flicker like x-rays.. then changes to another color hue.. flicker then another .. until after about 20 minutes the picture goes black! If we shut it off for 30 minutes, we can watch another 15 mintues before it starts again....
There is high pitched whine at start up.. but it goes away. The fan in the back where the vent holes are works.. and they replaced the lamp already. ( This is why I have it, they didn't want to invest anymore into it.)
So, here is my question. According to online forums it sounds like the colorwheel needs replacing. What do you think? The cheapest one I have found is $85 and well, a little skiddish about spending that without some direction from someone who knows.
I don't know how old these sets are....they have not made DLP for several years, BUT if additional cooling helps, then you've probably got a dust bunny clogging or just restricting the internal fans. Some sets have a slightly noisier fan setting which may be labeled 'high altitude' or some such. That setting increases fan speed.
You may want to check for such obstructions. The fans are supposed to be interlocked against restriction or outright failure.
As an aside, when I took my Sony SXRD apart, the cooling for the lamp and that air path was spotless and dust free.