No idea what's going on as that space is down at the moment, but unless you're running at something silly like 1024x768 then you won't be running at full detail, or even close to it. High detail is textures at or near max, everything else running at full and with 4xAA and 8xAA minimum. And I know you're only running DX9 (and your card isn't capable of running DX10 anyway) so you're not even running the best shaders before we even get to textures.
There isn't a PC on the planet which is capable of running FSX at full detail with acceptable frame-rates (say the min frame rate is 40fps with an average of 50fps) at a respectable resolution (1680x1050 minimum). That may change in the next month with 2 HD3870X2s (so 4 GPUs) on a X48 motherboard or 2 9800GX2s on a nVIDIA board (whatever board it is that allows 2 of the new GX2s).
Edited 1 time(s). Last edit at 01/20/2008 10:57AM by gav.