The appearance of the ZX Spectrum 128 is similar to the ZX Spectrum+, with the exception of a large external heatsink for the internal 7805 voltage regulator added to the right hand end of the case, replacing the internal heatsink in previous versions. This external heatsink led to the system's nickname, "The Toast Rack". New features included 128 KB RAM with RAM disc commands, three-channel audio via the AY-3-8912 chip, MIDI compatibility, an RS-232 serial port, an RGB monitor port, 32 KB of ROM including an improved BASIC editor, and an external keypad.
The appearance of the ZX Spectrum 128 is similar to the ZX Spectrum+ with the exception of a large external heatsink for the internal 7805 voltage regulator added to the right hand end of the case replacing the internal heatsink in previous versions This external heatsink led to the system's nickname "The Toast Rack" New features included 128 KB RAM with RAM disc commands three-channel audio via the AY-3-8912 chip MIDI compatibility an RS-232 serial port an RGB monitor port 32 KB of ROM including an improved BASIC editor and an external keypad