Gigabyte Radeon X800 (GV-RX80256D).
 

Gigabyte seems to be making a push to be a favorite video card vendor among people who want a silent PC, like those with a home theater PC or those who have spent a lot of extra money on other quiet components. Both are very good reasons to get a video card that is as silent as possible. Noise from a cooler always comes from the fan, so the best way to make a cooler quiet is by making it fanless. Gigabyte has done this with their Silent-Pipe technology. Essentially, it is a heat pipe design that pulls heat away from the graphics chip and transfers it to the back of the board. This makes it a completely silent video card.

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