in the video you can see that it amber blinks orange, not sure if the first blink counts but if it does the sequence is 1,3,2 then repeats or 3,2 which ever one. I’ve looked at the dell website and it says that 1,3,2 is a ram issue and I’ve tried all 4 sticks one at a time; Not sure if all of them are bad? 3,2 would be my gpu not working but the fans spin. I took out the cmos battery for a bit. I just got the master cooler 212 and it fits okay. New ram sticks wouldn’t be a bad buy but I think it’s unlikely that all four don’t work. Here’s a link to see the blink patterns-
View: https://imgur.com/a/wkqYe4m