Trying to help here. Many may already know this and these suggestions are likely mentioned elsewhere as well, but here goes:
Some tips besides the setting adjustments as mentioned in the FAQ for those having issues and trying to grab a couple more fps:
If you already are playing with high resolution, turn off or lower your AA settings on your card. It's not really necessary to AA much (or at all) with high resolution anyway (you shouldn't really notice that much of a difference), and the extra processing power you give to your GPU by lowering it or scaling it down may actually help.
Try experimenting with different screen resolutions. The rule of thumb that the higher the resolution, the better it runs for CFS3/OFF may not be the case for you. For me, the sweet spot is actually quite a bit lower than my monitor will allow (1280x960). Going higher than this negatively impacts my FPS and I get no benefit going lower than this resolution, in my case...may be the same with you.
Turn off unneeded and extra processes running in the background. A utility like End-It-All 2 or FSautostart can really help in this regard.
If your card supports it, and you are comfortable doing it, try a modest overclock of your graphics card using the ATI overdrive in your catalyst control center. Just tried a modest overclock yesterday, and got perhaps a 3-5% increase in FPS (every little bit counts). Careful with this though, as it can create an unstable system and will increase the heat of your GPU - test thoroughly beforehand and I suggest trying small increases first.
Again if you are comfortable, try overclocking your cpu. Some cpu's and systems overclock better than others. Same cautions apply as GPU overclock. Small steps first, I suggest...and test thoroughly.
Fly a different aircraft. Some are harder on FPS than others. For example, you'll get higher fps with a DH-2 then you will with a Bristol F2b (both in cockpit and outside). If you are desperate, though I don't recommend it personally as it ruins the immersion for me, fly with the cockpit off.
Make sure you have a nice clean install of your video card drivers. When updating drivers, parts of the older drivers will often be left over and can cause problems with newer drivers. Make sure the old driver is completely uninstalled first before installing a newer drivers. Various utilities on the internet, such as "Driver Cleaner" help to completely remove all artifacts of old drivers before new ones are installed.
Hope some of these tips are helpful.
