White pixels or dots on the screen i have a dell 4210x projector

Anything is usually fixable. What you have to determine with Dell's assistance is if it is cost effective to do so.

This is going to be the lamp itself. Once you replace it will have to be reset back to zero hours to work properly

Internal short switch was tripped, just do a factory reset.

Dell projectors are known for using extremely cheap display chips... Most probably the pixels are stuck you will have to send it to dell for service

This is a dlp projector and has a bad DMD chip. Most models are very similar. Here is a video of a similar repair.

I have 2 NP-200 projectors installed in a school which show white dots on a black background and black dots on a white background. This is caused by the DMD chip losing pixels. Only solution is to replace the chip, I'm researching now if that i an economical solution.

Need more info. But initial suspicion is there is a problem with your projector.

Are they stationary and always in the same position? You may have bad pixels.

Are the dots there with no signal going to the projector?

What is connected the the projector? Detail the video path - try all the sources. The dots still there and in the same position on all sources?

It is probably your projector.

If some of your sources are fine - the problem might be from a connected source.

Hope this helps.

perhaps it is the reason of DMD chips,
if the DMD chips had been bad, it will show some white or dark dots on the screen, it looks like that this machine need 1076-6038B DMD, but I can't make sure. so need you to find a repair man help you to reconfirm it.
this DMD is not expensive, so please don't be worry aobut it,

you can contact me for original DELL 4210X projector color wheel. i know the source, it is very cheap.

Have you checked the air filter for dust etc

what leds come on as it shuts down.
I suggest that you take it down and run it on the bench normal way up and see what leds come on etc