Also make sure you run Aces High on the same resolution and color depth with your Desktop. Usually that gives a few extra frames compared to differing setup.
If you get micro-freezes on screen during play, try playing with AGP aperture size. On some systems small size (32Mb) gets better results, some have to set it to 128 or higher..
Overclock that TNT as far as it goes.. If it breaks down, it's a good excuse to upgrade

Take into notice that there's a small chance of OTHER system damage if that happens, but I'd oc it anyway.
You can also look for hints at
www.3dfiles.com / utilities / tweaking
If you have the cash, take the best display card you can get! Geforce2 non MX would be a good choice, albeit the prize is bound to drop due to the release of GF3.
ATI Radeon can be tweaked for good results, Geforce2 MX is no faster than old Geforce1, but still a valid budget option. I get 45-75fps 1024x768x32bit with my old GF1 SDR + celeron depending on the terrain I'm flying with.
New main in tower 67fps with w2k dx8a 11.01 drivers.