If you look at the back of your case youīll see the holes for the expansion cards (graphic card, sound card, etc). If you got about 7 or 8 of them then you can fit in an ATX board, if not buy a new case. By the way, if you are planning to upgrade your pc, make some budget free for a case where you can add some extra fans in the future for some good airflow. For ~Ģ40-45 you can find a low-budget Miditower case at any pc-shop.