I've tried different things in the search engine. I don't know if it was here or on SimForums. But Nick posted about something you can turn off in UTX that he discovered (I think fairly lately)was a stutter source in FSX. It was not one of the traditional things, like turn back sliders, etc. It was something specific in the UTX panel that needed turned off, I think. This is not about performance hits ... this one was addressed a stutter source. If anyone remembers, could you please give me the link? Thanks, Steve

This may be the post that you are looking for: http://www.simforums.com/forums/forum_posts.asp?TID=29041&title=setting-up-fsx-and-how-to-tune-it (at the end) NickN makes comment about car traffic and performance and night lighting at certain intersections. NickN's quote: "The UTX NIGHT LIGHTING (and Cars) feature has the most impact on performance"RegardsPeterH

This may be the post that you are looking for: http://www.simforums.com/forums/forum_posts.asp?TID=29041&title=setting-up-fsx-and-how-to-tune-it (at the end) NickN makes comment about car traffic and performance and night lighting at certain intersections. NickN's quote: "The UTX NIGHT LIGHTING (and Cars) feature has the most impact on performance"RegardsPeterH

Thanks very much, Peter. No, unfortunately, that is not it. This comment was not in his well known Set-up topic on SimForums. I was not about performance, but stutters. I'm all but certain that this comment by Nick was more recent than that. Maybe not. But in any event I cannot remember whether it was Nick's own thread or a comment he made on another one. The gist of it, as I remember was that such and such a tweak [turning something completely off, I think] could result in a stutter reduction -- not an FPS issue, just a little better smoothness. I read it last week and forgot to bookmark it, and now I can't remember.Edit: I think you may be right after all Peter. Thank you. Here is the paragraph I was looking for, I think:"Cars are the primary perf killer. Ships and boats do present more for the system to deal with but most can run ships and boats between 15-25% without any problems. Cars on the other hand will create micro stutters in some areas depending on the hardware and addons like UTX must be used with caution due to how they can change car traffic behavior with their updates. Their UTX USA 1.2 update added cars to all side roads and in order to make that work they had to deal with a bug in FSX which removed the ability of FSX to take the footprint of cars off the system with the slider set to ZERO, therefore with UTX USA/CAN you must DISABLE ALL moving traffic in the UTX configuration tool to check or eliminate the source of micro stutters related to car traffic. If you find your sim smooth with it DISABLED in UTX then you need to evaluate CAR traffic use with your hardware."I'm going to experiment with this.