When looking for a video card from which the most that would be expected would be to play 1080p movies at 1920x1080 without stuttering, what sort of performance would one need to look for? I'm not asking specifically for examples of cards, but rather how to tell if a card or which cards are what you need, and what the limit is above which you would go overboard with performance.
More aboutwhat video card viewing movies
HD4350, HD5450 and HD5570 are all good for that purpose with HD5570 being the most powerful.
Anything that requires a 6-pin is overboard. Anything that isn't PCI-E is underboard.