I think I mentioned it before. When will Renoise be ready for multiple cpu support? To me it sounds like an easy thing to add.
The problem could be to decide how the cpu load should be divided.
Well it’s definitely not easy… But Renoise might be a bit more responsive with multiple processors, since it’s a multithreaded program. In overall I’d guess you’re better off with a faster single processor than with two. Perhaps someone with a multiprocessor system will care to test?