I previously bought the DD waterblock for the HD2900XT and it performed beautifully. I actually think that this one is EVEN BETTER! I too idled at 60c+ and around 90c under peak load on a single fan cooled 4870X2. Now my idle is around 39c and around 53c under harsh OC'd load. Great product!
The FB (Fat Boy) Fittings from Danger Den are now the most reliable and universal fitting to date. The FB Fitting integrates an O-Ring capture to seal. Large ID bore for high flow and lower pressure drop compared to other fittings. Designed with a G 3/8 BSPP straight thread.