i am going to be putting together a car PC and am looking at some mini itx boards but just a bout none have a composite out for the video. ( i need it to feed video into aux in on the nav screen)

i see that you can converts dvi to VGA and you can convert VGA to composite...BUT can you go from DVi to VGA to composite all at once??

it is a possibility that i MIGHT be able to use the analogue RGB inputs (NTSC) but iid probably have to set the sync speed sorted by possibly using a small circuit board and a 555 timer....i am not sure if i can get full stereo audio by using the RGB nav button instead of the aux in composite.

can the bios settings and or software sort out this stuff? i dont want to spend big bucks on commercial adaptor boxes as i might as well replace the head unit if thats the case.