Re: FreeBSD 6.1-STABLE & nvidia-driver: A couple of issues.
Why are you trying to use 1600x1024 with that monitor? I have the same monitor, the correct resolution is 1440x900: I had to make a "custom resolution" with the nVidia drivers to be able to set it. Mind you, this was in Windows.
I would try changing the resolution to the one specified by the monitor.