Honeywell-NEC Supercomputers Inc yesterday wound up the clock to 6nS on the low-end models of its SX 2 supercomputers, increasing performance of the smallest two by 16%, so that users can upgrade from bottom to top of the line, and expanded extended memory fourfold to a maximum 8Gb. All models are now fully field upgradable to the SX 2-400 (formerly the SX-2), rated at 1.3Gflops to make it the most powerful uniprocessor around.