I don't think you need a patch Dario Andrade. Try this instead.
Open your cards.txt file in the GP3 folder. Your cards.txt might look something like this:
[general]
[ASUS AGP-V7700 Pure/Deluxe v6.31c]
bilinear=1
loresclouds=0
detailmap=1
Add the following line, under the card your are using.
detailmap=0
Don't add anything else! Your cards.txt will be different from mine, and it supposed be that way! So when you are finished it should look like this:
[general]
[ASUS AGP-V7700 Pure/Deluxe v6.31c]
detailmap=0bilinear=1
loresclouds=0
detailmap=1
Save and exit. Start up GP3, and see if it works. If it does not please post again.
It's only after we've lost everything, that we are free to do anything.