You need a full college course to figure out the designations of the Evga Power Supplies. Obviously the watts ere self explanatory but what comes after that can drive you crazy. Nova G8, 8+ etc. does have some meaning. The internet has several sites that will explain the differences, but after reading several myself my quick answer would be they tell you who actually made the power supply FOR EVGA. They don't make the units themselves only market them. And there are apparently 6-8 different makers they use.
Not to say anything negative about this arrangement but it does get confusing when you want a 1000 watt supply, you know the level gold - but now you have to choose which actual maker?