With everything maxxed @ 1600x1200 and 8xAA, 16xAF, I get an average of 10 fps on the deck & about 50 @ 20,000ft 8)
Sadly, the machine I get this with has a 6800GT 256MB card, it makes my GF FX5600 look laughable! :-[ ::) and its not mine! - I've built it for a friend.....
Despite the differance in cards Steve_Butka, your system should handle FS9 superbly, Update your Graphics card drivers, Direct X 9c is now out, that could help....
Ultimately, its settings, even with my FX5600, with the correct (i.e. very low !) settings, I can get upto 100fps at zero feet, it just looks awful!

The XP3200+ (If thats what I think it is....) is no crap CPU, nor is the rest of steves pc for that matter! ;)

Posting drivel here since Jan 31st, 2002. - That long!
"He who laughs last, thinks slowest."