I don't think we have hit the limit yet. If anything, its soon to be a wakeup call for Video card makers. Intel and AMD already did this race once where they pile on the features and forget the power usage/heat dissipation. Now they are much more energy concerned, leaving their CPUs in the 65-120W range. Video cards now-a-days are drawing insane amounts of power, one can only hope that some day they will decide. "Humm, instead of adding another power slot, maybe we can re-design to make this use its current power more wisely".