I changed the RAM to two Kingston 8GB each. Previously, there were two 4 GB RAM. So, I sorbbed the computer back - the keyboard does not work, and the monitor just has a light that it is on, but it does not show anything, just a dark screen, while the system unit itself is working. And even if you connect the old RAM, the problem is the same. Looks like some settings got lost or what? When assembling, I disconnected absolutely all the wires and turned off the power.
Diodes on the mat board, see which ones are on. Check all loops and wires, maybe accidentally touched. Try to change the opera's bars in places, sometimes it is buggy.
