I just bought vga to 3rca cable to connect my laptop to tv. The colors on the 3rca end doesnt match the sockets on tv, so i dont know witch color is for video witch is for audio. tried to connect them " cris-cros" didnt work. please help
As it stands, that device will not do what you need it to.
They make boxes that convert VGA(D-sub) to Composite, but they are pricey and need there own power source.
Depending on your video card, you may be able to get a passive(no power needed) cable that allows you to get the yellow composite cable(and normally a S-video cable as well) out of the video card, either way, audio will come from your sound card.