techPowerUp posted a review on the PowerColor Radeon HD 4830 512 MB
A quote from the article:
>> PowerColor Radeon HD 4830 512 MB Review
PowerColor's new HD 4830 features the same 640 shader pipes as the AMD reference design, but comes with a big dual-slot cooler. Also new is a native HDMI output which supports HDCP and 7.1 channel audio. Thanks to a PowerColor designed PCB the card will retail about $10 cheaper than the reference design from AMD.
>> PowerColor Radeon HD 4830 512 MB Review