This is firmware update version 2.0 and is the latest official released operation system by Alesis. This operation system update/upgrade requires one eprom chip as revealed in the article`s photos and the chip will be labeled to help you locate the correct chip socket. For more info, please check below.
You can check your current OS by holding [PROGRAM] + 
Version 2.0 allows use of the Alesis Sound Bridge software, which is a utility program, that compiles custom samples from a variety of sources into the QuadraSynth Voice format, and then downloads those Voices to an Alesis – compatible PCMCIA Sound Card via MIDI SysEx to a QS6, QS7, QS8, QuadraSynth Plus Piano or S4 Plus that is running V2 firmware.