From this article at AScribe :

“More than $4 million in equipment upgrades will shine 100 million pixels on Iowa State University’s six-sided virtual reality room.
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Iowa State’s C6 opened in June 2000 as the country’s first six-sided virtual reality room designed to immerse users in images and sound. The graphics and projection technology that made such immersion possible hasn’t been updated since the C6 opened.
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The new equipment – a Hewlett-Packard computer featuring 96 graphics processing units, 24 Sony digital projectors, an eight-channel audio system and ultrasonic motion tracking technology – will be installed by Fakespace Systems Inc. of Marshalltown.”