what is the difference bettween this card http://www.amazon.com/XFX-Radeon-Double-7770-Video/dp/B008UBRU6I/ref=sr_1_12?ie=UTF8&qid=1389324371&sr=8-12&keywords=radeon+hd+7770
and this one
http://www.amazon.com/XFX-DisplayPort-Dual-DVI-Graphics-FX777AZNJ4/dp/B009K274H6/ref=sr_1_2?ie=UTF8&qid=1389324371&sr=8-2&keywords=radeon+hd+7770
besides the first one having 2 fans
and this one
http://www.amazon.com/XFX-DisplayPort-Dual-DVI-Graphics-FX777AZNJ4/dp/B009K274H6/ref=sr_1_2?ie=UTF8&qid=1389324371&sr=8-2&keywords=radeon+hd+7770
besides the first one having 2 fans