The Xiaomi 4k, Wemax 4k and Fengmi 4K are a Chinese line of projectors based of some similar hardware components, in this case the DMD chip.
Projectors: Xiaomi 4k, Wemax 4k and Fengmi 4k
Reason: The manufacturers are using a weak metal heatsink plate that bends after prolonged use, causing a reduced heat transfer contact with the DMD chip that problems arise from.
Laser Projector shows Vertical Lines, Snow white dots, slow booting up issues or no booting at all.
Replace the Heatsink plate on the DMD chip.
How to Video: https://youtu.be/0i_YXaJRb_A