When i turn on samsung model HL-5675s sounds like it wants to turn on but doesnt. i opend the back. and they light turns on for like 3 seconds. the fan turns on. but thats all . not sure what it could be? and befor that it got a white dot on the left side of the screen. also turnd off by its self that last week and when i turnd it back on it did but sounded like it struggeld to turn on.

have you tried a new lamp?

Bad main board

My TV is (same model is doing the same thing). The manual shows that the 3 blinking lights indicate "LED may be defective. Please contact a certified technician."

Note: When I power my TV off (unplug) and back on, the TV's left indicator light is solid for less than a second ("Stadby state") then the right light blinks ("The picture will automatically appear in about 15 seconds") for about 15 seconds. This pattern is repeated numerous times (I think it was 5 times). I believe the TV must be failing some power-on test. Aftere failing 5 times it gives LED may be defective indication.

lamp, ballast or colorwheel

The most common failure in the DLP that makes a whining sound would be the color wheel. They cost about $135 + labor because I wouldn't advise changing it by yourself.

you may check your lamp first. other than that i would say a faulty mains board.

it was bad bulb

This sounds to me like one of two possibilities. First, check your ballast. If you're going through bulbs faster than you think you ought to be, you may have a ballast that is overloading. Its the 3" x 8" circuit board that connects directly to the bulb. They are plentiful and often cheap. Thats what I'd try first. If that doesnt' do it, I would invest in a new power supply board. That the board that the tv power cable hooks directly in to. This should give you a start, Comment back if you still need further help. Good luck.

sounds like the digital main board, seen this before

Could be a main board or a DMD board .