Overclocking

There are two primary types of Dreamcast overclock mods. One increases speed by 10%, and the other by 20%. The 20% overclock provides greater speeds, but requires some system peripherals to be overclocked as well (for example, a VMU will not function properly and may even corrupt saves if it is not overclocked alongside the system in this scenario).

10% Overclock

The 10% overclock is considered stable enough so that it is unnecesary to overclock accessories.

See this page on Dan's Projects.

20% Overclock

See this page on Dragoncity (French).