I am not sure if Vue can control # of threads like Lightwave. If so... It would be interested to compare the test with single thread on both machines and then compare the test with multiple threads on both machine. My guess if multi-thread will have better performance on hyperthreaded machines than on ones that are not hyperthread. Also you can tell the effect of hyperthreading by turning off hyperthreading on a machine with it. I would expected with applications like Vue and Lightwave which support multi-cpus that turning off hyperthreading will lower performance.