Just in case you guys arent following the tie fighter forum, i created a thread explaining how to activate 3D (which was clearly disabled by gog) for that game and this thread turned out to be very interesting and helpful for xwing too, thanks to the people of gog's community. thanks guys.

http://www.gog.com/forum/star_wars_tie_fighter_special_edition/reintregrating_3dacceleration_kind_of/page1