Thấy trên website nó hướng dẫn cách xuất tín hiệu Video từ vga card ra Component (DVD) - dây 3 màu.

Nhưng mình làm nó chẳng có tín hiệu gì cả

Ai rành cái này chỉ mình với

http://www.myhometheater.homestead.com/vgacable.html
Will I be able to use the VGA to component adapter to watch my computer on my big screen TV?
You can connect your PC to your wide screen TV if either the TV has an RGB (HD-15 or 5 RCA) input or if your computer can output its signal in component. Some video cards can do this natively (some ATI) or via a "dongle" (most Radeon cards), some NVIDIA cards have component output also. Bottom line: you'll have to check the specs of your video card. If there is no RGB input on the TC or component output from the video card, you'll need to get an RGB to Component transcoder, or scan converter (really two names for the same thing).