Okay, I have installed BT5R2 on dual boot, and when I go to monitor options I only have 800x600 and 1024x800. My actual max is 1600x900, so I went to /usr/share/xresprobe/xorg.conf and changed all the modes to 1600x900, but it's still the same. I checked it again, and it still says 1600x900 in that file.

Any workaround? Cheers!