The ATX standard has changed very little in the last 15 years, which means some rather old computer cases can still accept new motherboards, as long as you also replace the power supply.
The bad news, as I stare at the case that once housed a Micron Client Pro 766 Xi (a 266 MHz Pentium II that was state of the art in 1997) is that front-mount USB ports were unheard of in those days, as were digital camera memory cards. Instead, machines of that era used obsolete floppy and Zip disks for removable storage. They also typically had more 5.25″ bays than we need today. When CD burners cost $400, most of us kept a reader in as well, to avoid wearing out expensive burners prematurely.