More RAM... What If ?????

Pardon the question if this has already been covered a million times already, I don't stray over here to the Hardware forum very often.
What kind of increased performance might I see while running FS9 if I upgrade my RAM from 256 to 1GB ??
I ask because I'm curious if my money would be better spent on a better graphics card than my current GeForce 5600FX.
Will I even notice much of a difference in how FS9 runs with more RAM or will frame rates still be about the same without upgrading to a better graphics card?
My setup is a meager
P4 with 256 RAM and 80 GB HD and the GeForce 5600FX for graphics running Windows XP.
What kind of increased performance might I see while running FS9 if I upgrade my RAM from 256 to 1GB ??
I ask because I'm curious if my money would be better spent on a better graphics card than my current GeForce 5600FX.
Will I even notice much of a difference in how FS9 runs with more RAM or will frame rates still be about the same without upgrading to a better graphics card?
My setup is a meager
