An Optoma GT750-XL ,

SOURCE: dvd10 optoma projector makes a loud noise

Hi, I'm not sure if it's the same problem I had..
I had it on picture mute, for maybe 15 mins, which may not have been a good idea. While it was muted, it made a sparking sound, and then a very loud grinding noise. When turned off, the lound noise stops, and the fan continues as usual for about a minute. As soon as it's turned back on, the grinding noise is back. But the logo seemed to display ok.

I took it in for repairs, and they said they needed to replace the color wheel to fix the problem.

optoma dv10 mode

SOURCE: Optoma EP755 new lamp when power standby button

you need to reset the lamp timer, usually done by holding some buttons while turning on

SOURCE: optoma ep719

There is a stuffed 10v 3300uf capacitor on the power board. You need to replace it.
Bellow you can check in the picture where the capacitor is located.

Notice that in this picture I have already took the bad capacitor out and replaced with two small cords to reach the bottom and test the new capacitor.
To reach this place is not fast, several layers of plastic and metal must be removed, but is not a hard task to take the capacitor out and replace it for another.
It works just great! Now it is back on track with awesome image.

SOURCE: Optoma 719, can't get lamp and fan to turn on.

There is a stuffed 10v 3300uf capacitor on the power board. You need to replace it.
Bellow you can check in the picture where the capacitor is located.

Notice that in this picture I have already took the bad capacitor out and replaced with two small cords to reach the bottom and test the new capacitor.
To reach this place is not fast, several layers of plastic and metal must be removed, but is not a hard task to take the capacitor out and replace it for another.
It works just great! Now it is back on track with awesome image.

SOURCE: Optoma EP719 lamp does not come on

I have the same problem. The 10V 3200uf capacitor is bulged. Can't find one on the web. Where did you get yours?