techPowerUp posted a review on the Powercolor PCS HD 4850 512 MB

Powercolor's latest HD 4850 PCS graphics card is based on the AMD HD 4850 reference design but comes with an improved cooler and slightly increased core clocks. While the overclock makes only a small performance difference, the cooler substantially improves the product. Even under load the PCS 4850 is barely audible which makes it the quietest graphics card ever tested - of all performance classes.

Powercolor PCS HD 4850 512 MB Review