Given their nature, external water-coolers have a lot of room to do things right. Zalman took full advantage of the space they had with the XT and delivered a superb external solution with excellent performance. Though slightly expensive, "you get what you pay for" rings true here.
FULL STORY @ TECHGAGE (http://techgage.com/article/zalman_reserator_xt_hybrid_liquid_cooling_system/)
