With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Marilyn Burns acted.
text_B: Varian Data Machines was a division of Varian Associates which sold minicomputers .. Varian Associates. Varian Associates. It entered the market in 1966 ,. but met stiff competition and was bought by Sperry Corporation in 1977 .. Sperry Corporation. Sperry Corporation. The 620i and 620 / L series were parallel , binary 16-bit general-purpose digital computers with core memory expandable to 32,768 words .. core memory. core memory. An 18-bit word length -LRB- for data , not addresses -RRB- was optionally available .. A basic machine cycle took 1.8 microseconds , and the core memory read time was 700 nanoseconds .. core memory. core memory. The computers uses two 's complement arithmetic and had four main registers - accumulator A , accumulator extension B , an index register X and a program counter register .. Addressing modes were direct , immediate and indexed .. The instruction set had more than one hundred arithmetic , logic and control instructions and some variants supported microprogramming .. These models used a hardware front panel console that allowed starting and stopping the machine , examining memory and registers and changing memory or registers with front-panel switches .. front panel. front panel. The processor was made with integrated circuit transistor transistor logic from the 7400 series .. integrated circuit. integrated circuit. transistor transistor logic. transistor transistor logic. 7400 series. 7400 series. The system was packaged in a 19 inch rack and used 340 watts of power at 120 V AC .. 19 inch rack. 19 inch rack. The 620 / F was a variation with a faster machine cycle time of 750 nanoseconds .. The 620 / L -100 was released in 1973 .. It had a cycle time of 950 nanoseconds and a more compact system chassis than the 620 / F .. The Sperry V70 series had semiconductor memory but could also support core .. Various models were released between 1972 and 1977 .. Varian V72 computer systems were installed at Bruce Nuclear Generating Station as the digital control computer system which monitors and controls the major reactor and power plant functions .. Bruce Nuclear Generating Station. Bruce Nuclear Generating Station. As of February 2017 these were still in operation , and planned to be replaced by more modern systems in 2018 and 2019 .
not_related.