How do I set a codec's priority? (1 Viewer)

[Topher5000]

I rip my dvds to xvids using AutoGK. When I play them, the divx logo appears in the lower right corner, so I assume that it's using the divx codec. The quality's fine, but I'd like to try the xvid codec to see if it can be even better.
I know I have to set the codec's priority, but I have no idea how to do it.
Thanks in advance.

 

[gemx]

The priority is called "merit" in DirectShow terms.
A good tool to change the merit is the DirectShow Filter Manager
With this tool you also get a good overview about the installed codecs and are able to un-/install them