That’s when you use the ports placed on the motherboard in a standard verical PC case, meaning the system uses integrated graphics for the visual output instead of deticated videocard. Videocards that are put into MB at 90° are horizontal, right, but in most office setups I handle they are rare nowadays. Videocards are almost exclusively installed when you handle 3d and content rendering in demanding apps, and for office and browser stuff they are too costy after the crypto price hike and in a sanctioned Russia.