Sotorn:
I tried that with a cheapmod once, which had male pins on it. It seemed like a good idea, since I had an IDE cable which I butchered laying around.
The problem with using a pre-made ribbon cable is that the pins get reversed left<-->right when you try to do this.
It's kind of hard to imagine (at least for me), but if you have a cable, imagine the top right corner pin is the #1 pin and the one below it is #2. You put one end on the chip, and put the other connector on the motherboard. The #1 pin on the chip is connected to the #2 spot on the motherboard.
It would work if you made your own cable. I know this b/c after using the straight cable method, I tore off one end of the IDE cable, and soldered the proper wires into place on the LPC. It then became a wire adaptor with a female pin header connection.
That worked great to boot up, but I screwed up all my work when I tried to flash the modchip, and it kept freezing up, probably because of the length (and crappiness) of the IDE cable.
Anyways, long story short, a length of ribbon cable designed for IDE, etc, probably won't work. If you have some sort of straight connect cable, it'll do, but you might run into issues when flashing through the xbox.