The geforce 4mx isnt strictly speaking a geforce 4
the mx's were based on the same Graphic core as the geforce 2 and they have the same spec.
Geforce 4mx's are a directx 8 compatible card only,just because you can install directx 9 doesnt mean your card fully supports it.
I would consider a graphics card upgrade to at least a ATI 9800/se or a nvidia 5900xt, you might be able to play it with the current card but you would need to drop everything down to the lowest detail.
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