I bought a EVGA GTX 680 4GB FTW from newegg maybe around 6 months ago and I want to buy another one for SLI but I can't seem to find it any where... I searched on NewEgg and it's discontinued. Amazon is all used/really expensive ($3,000). I also checked pricewatch.com and they do not hold it and neither does tigerdirect.com... EVGA.com only holds the 2GB version of the FTW. Would I be able to use SLI with a 2GB and a 4GB version or does anyone know where to buy a 4GB version?