NCR Corp, Dayton, Ohio is stepping up its challenge in the high volume transaction processing market by signing for a joint venture with the leader in high-throughput back-end database machines, Teradata Corp of Los Angeles. The two companies have signed a letter of intent for a joint venture to exploit their respective skills in parallel processing in developing new general purpose computer systems, and the agreement is rather more far-reaching than ones that Teradata has signed with other majors, because it involves NCR taking a stake of about 10% in Teradata by buying new shares – but NCR stresses that the investment is simply to cement the relationship and that it has no plans to increase its holding beyond 10%. Fast-growing Teradata had 1989 sales of $137.4m from its DBC1012 machines, which use an array of Intel 80386 processors to search a database at very high speed. NCR’s top-end 9800-XL mainframe is a multiprocessor machine for which fault-tolerant configurations are available, but the joint venture is likely to involve combining the two companies’s skills in the design of NCR’s next generation of Tower Unix machines.