 Like its predecessor, the Cray J90, the SV1 used CMOS processors, which lowered the cost of the system, and allowed the computer to be air-cooled.The SV1 was backwards compatible with J90 and Y-MP software, and ran the same UNIX-derived UNICOS operating system.The SV1 used Cray floating point representation, not the IEEE 754 floating point format used on the Cray T3E and some Cray T90 systems.