what the small white thing in this 7970 gpu picture ?
http://www.tweaktown.com/image.php?image=http://imagescdn.tweaktown.com/content/4/8/4883_07_sapphire_radeon_hd_7970_ghz_edition_vapor_x_3gb_overclocked_video_card_review_full.jpg
http://www.tweaktown.com/image.php?image=http://imagescdn.tweaktown.com/content/4/8/4883_07_sapphire_radeon_hd_7970_ghz_edition_vapor_x_3gb_overclocked_video_card_review_full.jpg