I just can't help myself here. There have been countless guides, videos and help via Nick N on how to get FSX at high frame rates using full AI.
Like Nick Needham says the problem is not FSX it's your computer. Do you have to spend a fortune to get what you want-NO!
There is an old General in here, WH61 on the forum, who runs great frame rates with tons of AI via Ultimate Traffic and My Traffic 2010 all on full with an E8400, Gigabyte X48 motherboard, an ATI HD3850, 4GB DDR2 1200 RAM most sliders full right except Autogen at DENSE that I built two years ago. His secret to running high fps with full AI is simple. Get rid of the defualt AI and replace with the new AI offered on MyTraffic and Ultimate Traffic.
I run high fps all over the place, in New York in a storms etc., with a Gigabyte X48 DQ6, OC'd Q9550 running @ 4 GHz, a GTX 260 Black Edition OC, 4GB Patriot DDR2 1200 RAM again all sliders right 70% AI (because I use default FSX AI) that I built over a year ago. I have posted the pics and sliders countless times. It isn't rocket science. There are countless others, but you guys that are stuck on the notion that FSX needs a super computer are just wrong. (by the way these are locked fps, on unlimited you can run a true 60 or better in most places, but it will dip running unlimited in places)
Lionheart is trying to run FSX with a 128 bit substandard video card on a MAC notebook using Bootcamp which sucks his resources dry. I repair and build PCs and MACs I know what they will do and won't do. If you want to run a MAC get a MAC with a Xeon Quad and the new GTX285 or HD4890 video card for MAC. You'll spend a fortune with a MAC but at least you will have a MAC that runs FSX very well with the new Snow Leopard OS
http://www.apple.com/macpro/specs.html
Look, the guides are on the FSX side if you want to learn. Nick N's guides are at simviation forum if you want to learn. I am not saying that FSX is the end all do all, but most developers now will tell you they only build FSX because it has the most potential. Take a look at what A2A has accomplished with Accusim and some of the new realistic modelling that REAL AIR and others are doing.
Default FS9 and FSX basically suck from a scenery standpoint, so you can't just point a finger at FSX default and say it's lousy-so is FS9 with it's stupid leopard spots on the ground. It takes addons to make these two sims really shine. We have great addons for both now and they do look great especially when compared to X-Plane, Flight Gear and host of other wannabes-although X-Plane is catching up fast with better looking aircraft, scenery, and AI traffic.
If you like FS9 stay there, if you want both FS9 and FSX you can have both and it doesn't cost a fortune. But bashing FSX and saying it isn't as good as FS9 is just simply in error. FSX is a better product in many ways, especially from the developer side. Now that Microsoft has announced no FS XI there has been more time to develop for FSX without the pressure of obsolescence.
Approach FSX like you approached FS9, with an open mind, and get help when you need it and you may find it to be a great experience. I remember all the bitchin' with FS9 came out from all the guys that were still using FS98 and FS2002...remember? The FS2002 guys were saying how slow FS9 is, and how bad the scenery looked compared to FS2002. Looks like history is repeating itself again! I'll get off my soapbox now.
Ted