When we first tested NVIDIA's new 8500 and 8600 Series we quickly realized that the power consumption of these cards is quite low. Zotac used this feature to their advantage and put a passive cooler on their cards to remove any annoying fan noise. This adds additional value to this midrange segment video card.
ATI's Radeon HD 2000 Series features additional audio output over HDMI. To ensure that their product can compete with ATI's offering on the Media PC market, Zotac added an external audio input that mixes the audio signal into the HDMI signal on the DVI output. While the ATI solution generates the audio inside the GPU, Zotac's card requires an external audio source like on-board audio or a normal sound card.
Performance-wise there are no suprises, the card performs like a typical midrange card with support for DX10 and Shader Model 4.0 (not that anybody would need that today or in the next months). Overclocking potential is slim, but can still deliver nice extra performance - if you ensure proper cooling.
With a price premium of about $10 this card is certainly worth its money especially if you consider that you can finally get rid of the annoying fan noise of your video card. With that price difference you can barely buy an aftermarket passive cooler. Even if you found one you would have to install it yourself, which voids your warranty.