An aging computer — so old that the University of Washington has an early model on display as a museum piece — stands between the Seattle School Board and the changes it wants to make in how the district assigns students to schools. The computer, called a VAX, was first sold in the late 1970s. The district still uses two VAXes of late-'80s to mid-90s vintage. They use old-fashioned disks and stand about 5 feet tall. Staff members sometimes look for used replacement parts on eBay.