The H.264 Codec In Windows XP And Windows Vista
Wow, it doesn't get much closer than that. All of the cards are offloading a huge amount of CPU resources, with the demanding H.264 codec only requiring about 25% of the CPU's power to play it with these accelerated cards, as opposed to about 75% of the CPU's resources when acceleration is off! The GeForce 8400 GS is struggling a little bit compared to the other cards, but still relieves the CPU of most of its load.
Vista equalizes the playing field for the cards, with the 8400 GS delivering identical performance to the other solutions. There is only a slight increase in power required compared to XP: about 10% more CPU capacity. The success of these cards is still phenomenal when compared to unaccelerated CPU-only video decoding.