Look for a special connector on the motherboard. It's used for the led's, reset, and power switch, etc. Also, check the ports on the back of the case. You can easily compare them to photos in boards listed at newegg and other venders. Your Gateway case may have a removable section for the custom backplates that come with most new boards. If you can use a backplate, then it's possible to rewire the main leads using a splicer and inexpensive components from places like radio shack. Before you do, checkout the power supply. If it's less than 300 watts, I would just replace the case. You can get a case for not much more than a new power supply.