Silicon Graphics Inc has brought the entry price for a RISC-based three-dimensional workstation down to $50,000 with launch of the Iris 4D/50. The station combines 8MHz MIPS Computer RISC with Silicon’s Geometry Engines, and is rated at 7 MIPS. $49,900 buys 8Mb CPU, 8 colour bit planes, 170Mb disk, Ethernet and 19 1,280 by 1,024 screen.