CrystalCT Rertro Productions developed a test cartridge for the Commodore C64 computer, based on the Dead Test by worldofjani.com. The cartridge starts the C64 in the Ultimax mode, executing the code in the upper 8 kB of the EPROM. This can be the Dead Test or DesTestMax code. Then it will switch to the Standard mode, and executes the code in the lower 8 kB of the EPROM.