International Business Machines Corp. confirmed that it...

International Business Machines Corp. confirmed that it plans to accept its old XT and AT model personal computers as trade-ins for discounts on its new Personal System-2 line. The trade-in program is apparently intended to hasten the acceptance of the Personal System-2 line--introduced in April, 1987--as a new industry standard. Although PS-2 sales have been healthy, there is still strong demand for computers built to the old standard, such as the XT, the AT and compatible models made by such companies as Compaq Computer Corp. and Tandy Corp.