Color depth

[Daniel Borgmann]

Hello!

First of all, great port of course. :) 
In my everlasting quest to get some decent performance out of my 1000
Mhz CPU (I already play without sound!), I'm wondering if the 16 bit
option actually does anything. I see absolutely no difference and
framerates also don't change when selecting 16 bit instead of 32 bit in
the game. Also, I saw someone writing that he started his X server in 16
bit mode to get faster FPS.
Now I'm wondering, does the setting in the game actually do anything or
do I really have to start the X server in 16 bit mode to get a lower
color depth? 
On a related note (but off topic), does anyone know how to enable vsync
with XFree and Nvidia driver? I couldn't find any infos about this in
the net (searching for vsync and xfree isn't very productive :/).

Thanks,
Daniel