You may as well try the newest drivers - I wouldn't expect Nvidia to be trying too hard to help someone play a 4 year old game - even if it is the best racing game around
So you COULD try emailing them....actually yeah it'd be good.
What version of Direct X comes on the GP3 disc? I think it's 6....so email nvidia, asking them which drivers would allow best compatability / performance of a DX6 (just as example) game, using a FX5200 card - which is dx9 compatible. They'll probably say they're backwards compatable - and if they have no better suggestions, then just load up the newish drivers (the reference ones which came with card, say) and give it a go.
I'm not sure whether the new GeForce cards will even like the old drivers - as your 700% PO suggests. I know the old cards work with new drivers, but new to old I don't know.
Well, I'd be interested to find out - let us know how it goes
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She says brief things, her love’s a pony
My love’s subliminal