I noticed that I've used 24 bit, but does it also support other depths like 8, 16, and 32 bit as well?
yeh i think it does. not sure if it will go as high as 32-bit before but TA5 probably does.
At that point though, in a game like this its not really worth it... I use 24-bit myself. Note that when you cut down, you might loose certain features such as alpha channels (im pretty sure it has to be 24-bit or higher to support alpha channels)
32 bit is the only one that supports alpha channels at all...
24 (i.e. opaque textures) or 32 bit (textures w/ alpha channel, i.e. transparency) are best. DirectX upsamples textures to one of those formats, most of the time anyhow. 1.2 reads in a few formats/depths, 1.3 reads in a whole lot more.
-- GSH