Getting my color depth to stay put

[SirPeale]

I have a computer hooked to my TV set.  I use it as a media player.

It's set for 640x480 res, and comes up that way each time.  What doesn't come up correctly each time, however, is the color depth.  Always 8 bit.  I have to manually set it to 32 bit each time I turn it on.

How can I get the color depth permanent?

[retrometro]

actually i have a similar question to the community. ... assuming your computer and video card is relatively recent, is there an advantage to run under any particular color depth other than 24 or 32 all the time?