My new X99/i7 build is working quite well. As much as I prefer Windows 7, I bit the bullet and moved the new rig to Win10. While the UI can be a bit annoying, most of my reading supports Win10 being a leaner and better OS. I can't see any reason that older versions of PT would not run fine(but having said that, the features that you are missing in PT9 as compared to 11 and 12 is pretty stunning. Since you are going to build a new machine, you might consider it a good reason to also update PT. Besides Clip Gain, Track Freeze and Track Commit(all "game changers" to me), the raw horsepower gain with full 64 bit software is pretty amazing
(of course, every plugin would need updating, so I understand your reluctance)
