Although the GTX 650 Ti and the GTX 650 Ti Boost share the same number of CUDA cores and very similar names, they are actually very different cards. With the addition of Boost functionality and a jump in base clock speeds the Boost is bound to outperform the GTX 650 Ti. Along with that you are also getting twice the memory (there will also be a 1GB versio of the boost as well) and a 192b memory interface over the GTX 650 Ti’s 128b interface. That gives you an improvement in memory speed from 5.4 Gbps to 6.0 Gbps. On top of it all, they don’t share the same PCB’s or cooling, in fact they are considerably different in size all together. The reason for all of this is actually very simple and obvious when you see the specifications listed out alongside of the GTX 660.