The only way you can re-use an old PC case from the 90s is to heavily modify it with new fan mounts, removing the internal cage for airflow, and other requirements, making it quite the undertaking.

Coolify has apparently put those spinning LED displays—the ones that are a bit flickery and sort of transparent since they’re made with spinning bars—on a PC case fan. PCWorld’s Mark ...

A motor-driven fan that is part of the computer case. Contrast with fans that are attached to the CPU or graphics chips. See fan and CPU cooler. THIS DEFINITION IS FOR PERSONAL USE ONLY.