So, I have a double monitor computer. It was starting to collect too much dust inside so I decided to clean it carefully. I removed everything, including the motherboard, and put it back properly. I turned it on and it was booting normally, but later on I found out that only 1 of my monitors was being read. It was the monitor connected to my motherboard. The other monitor connected to my graphics card wont display the second monitor. I switched the monitor cable that is connected to the motherboard to the other monitor cable that is connected to the graphics card, and still, the only monitor being displayed was the monitor connected to the motherboard. I tried re inserting the graphics card multiple times, yet it still wont read the monitor. I tried it with only one monitor. I first tried the 1st monitor cable. I connected it to my motherboard, it booted perfectly. Then, I connected it to my graphics card, nothing showed. I, then, used my 2nd monitor cable and connected it to the motherboard and the graphics card, individually. Results were the same. Both the monitor cables was working perfectly. The problem was that my graphics card can't read/detect the monitor cables. I have no idea how to fix this.