Each manufacturer takes their own approach - many simply add their own cooling solution, others may OC the CPUs to a higher level - some like EVGA bin the GPU chips to offer them in a variety of packages at different pre-OCs and cooling designs
The cooling and maybe overclocking depending on which card you choose. It doesn't massively matter if you are using water cooling or are not too bothered by an extra 5 degrees
Each manufacturer takes their own approach - many simply add their own cooling solution, others may OC the CPUs to a higher level - some like EVGA bin the GPU chips to offer them in a variety of packages at different pre-OCs and cooling designs