Problem Xbox On Beamer = Screen Kind Of Green Options

[syro]

hi guys.

I've a big problem. I'd like to connect my xbox on my beamer via vga to get a better resolution. so I bought a component cable (like hd pak) and connected it on the xbox. my beamer has only to two inputs rgb and vga. so I bought a cable that changes yuv (component) to vga. I connected both cable with an adapter so the signal can go from xbox to my beamer. but here is the point when I turn my beamer on - the whole screen turns kinda green. I see the xbmc or msdash but whole in green. I don't know what to do. please help me. do I need a special bios or something else? I've a xbox 1.0 and a matrix/xodus chip -> has only 256.

- sorry for my english - I'm from germany

greetz syro