Maxent MX-26X3 picture problem

Someone gave me a maxent mx26x3 with the same problem. I took the back cover off, and then the metal shield covering the PC board. There is a green heat sink on the main processing chip. The heat sink was not making good contact. I slightly twisted and pushed the heatsink on the the chip, and the picture stayed perfect now for 2 days. I think the heatsink will eventually need to be re-glued on with thermal expoy glue. It will be a pain to remove and clean though.

The heat sink is not the real problem i tried this fix and it worked for a week and then became worse the connectors on the chip under the heatsink become disconnected due to heat and lack of ventalition the only real fix is to re-solder those tiny connectors which can be done but is quite difficult you have to use special equipment just to see them clearly.

Sil2222 is right about the problem being in the solder joints. I have fixed several of these by using my hot air solder station. You have to put pressure downward with the handle of a screw driver while reflowing the solder and keep the pressure held until it cools. Do all four sides one side at a time. Do not allow all four sides to flow at once or the chip will shift.

We followed the advice of seto, & it worked! Removing the stand (it slides out of the back) was also necessary. We also carefully vacuumed the dust out. Thank you, thank you!!

I had lines running down the screen so I also took that back cover off with the mx26x3 and the green heat sink had come loose. I twisted it and pressed it back on an it seems to be working again.

After reading the other solutions I took it a step farther. By placing a small 12v fan out of a small printer or in my case an old Cisco 2900 switch. This fan was mounted into the tin shield that covers the whole board. I piggybacked onto the other fan using telephone splice connectors. I also drill small holes in the plastic back cover and now it pulls the hot air out.

Now let’s see how long it will last.