Actually many cables have twin white cables. As these are data cables, you will not damage anything if you connect them the wrong way round - it just will not work. Connect the outer cables as I have and the centre one as shown in the diagram also - sometimes there is just one. As your Sata cable is flat, it should be pretty easy to distinguish what the wires are. If one or both of the USB ports do not work, just reverse the data cables till they do.
You do not want to connect the red wires at all. The power is already supplied to the front panel. If you look at my diagram it says "no connection". The + and - are supplied independently of the USB header. You could always find a donor cable that does have the main earth wire connected, failing that, connect the central grounds to the other 2 existing grounds respectively.
3.3v is for firewire and 12v powers the various hubs onboard. You can either piggy back of the main motherboard plug with the appropriate connectors or scrape some of the insulator away solder and re-insulate or use shrink tubing over the solder joint. For the audio port there is probably a "USB" looking type connector on your motherboard which carries HD output. You will need to refer to your motherboard manual which will give you the pin layout. The red cables for USB are left unconnected as that voltage is supplied already.
piggy back connector sometimes used in automotive situations for audio - leaves the cables virtually undamaged.
I know what you mean but can I connect the red wires from the motherboard's usb connectors to power pin no.4 ? so that I dont have to piggyback a wire frm the motherboard's connector. actually any 12v source is fine right (molex)?
Does the front panel need to be powered by the 12v, 5v or 3.3v if i want to test out the audio port? if so, which is it? I've been trying the audio wiring but it doesnt work even though I've both possible combinations.