IPL Systems Inc has stopped investment in its IBM 4300-compatible mainframes to concentrate on the IBM System/36 and System/38 add-in boards and peripherals markets. President and chief executive officer Bob Norton says that IPL will continue to manufacture the CPUs until its two major OEM agreements, from AT&T and Masstor Systems Inc, run out next summer. While not ruling out a move into the IBM 9370-compatible arena, Norton says IPL is preparing to branch out in the S/3X peripherals market to supplement its income from System/36 and System/38 memory enhancements as the 4300 market is coming to an end. The 4300-compatibles, which are built in-house unlike the memory boards which are contracted out, still account for 75% of the business, but Norton says he is optimistic about a future without the CPUs. Claiming a unique design that allows us to keep the cost very low, Norton says IPL is 50% cheaper than IBM when it comes to S/3X upgrades. After a rough time in 1983, 1984 and 1985 when it lost $4.3m, $11.9m and $3.2m respectively, on turnovers of $9.9m, $4.6m and $2.5m, IPL climbed back to profitability last year and in the 1987 first quarter reported net profits of $419,000 on sales of $1.1m – six month figures are in page three. From a high of 260 staff in 1983, the Waltham, Massachusetts-based company founded in 1973 with finance from Control Data Corp, now employs just 24 people.