Graphic freez hard reboot!

[zawardo]

I have italian version (so i can only have 1.6.4 native version or 1.7 patch), with 1.6.4 che game crashes to desktop as soon as i enter the 3d map; with 1.7 it does work but freezes randomly when a dialog overlay appears. I've tried anything: citybuilder config, newsest vga drivers, 4:3 aspect ratio, lower settings...etc
It's always the same, random freezes. I have one of the firsts athlon x2 4400+ and a 8800gt.
I've played several hours (i'm level 8 ), but the freezes are getting worse, today it does always freeze after few minutes, i suppose the only chcance is a new patch.
it's so sad a game so good have such issues which definetly prevent me from being able to finish it