Here I have an older 2001 Barco ILite 10 LED tile that's part of a much larger videowall.
The I10 tile has a 10mm Pixel (LED) pitch, Each single LED package contains 3 LEDs, red, green and blue.
There are 44 LEDs on both horizontal and vertical access meaning that there are 1936 single LED packages.
16 LED boards make up the front of the tile and each LED board has an 11 x 11 LED grid, the black plastic that surrounds the LEDs is known in the industry as a "shader".
Behind the 16 LED boards is a large metal chassis which forms a heat sink, then there are 4 LED driver boards, each driver board controls 4 LED boards.
The Driver boards are home to the individual drive chips that run the LEDs as well as other local smaller processors which conrol the LED drive chips.
On the back of the 4 driver boards fits 1 larger central processor and codec board, this is the brane of the tile, it houses a small DIMM PC card which is like a miniture computer all on one plug in card.
A device called a "resync unit" or as we call them a resyncer plugs into the central processor board and this receives the video data as well as serial data all sent by DVI cables to the tile, it also bosts the signal and passes this on to the next complete tile in the wall, the resyncer is bi-directional so either socket can be used as an input or output.