Thermaltake's BigWater series of coolers has been commerically available for some time now, and has generally received some high marks for its cooling capabilities. Although adding in water-cooling to a system is not a novel idea, typically the base of the unit remains external. The BigWater 760is included with the Hydra has the advantage of being installed internally, using two empty 5 1/4" bays.
The main unit consists of a pump, reservoir, radiator and top-mounted 120mm fan, that is illuminated by a blue LED when powered. All of this is masked by a black front plate with a small mesh ventilation opening used for air intake. Air is pushed downwards by the fan through the all-aluminum radiator, which uses dimpled tube technology, swirling the coolant within the radiator in order to increase thermal transfer. While we liked the HYDRA labeling and the blue glow emanating from the vent, we once again feel that there's a missed opportunity here. So much of the space is used for company or product logos when it could have been used for temperature readouts or other controls. We're also a bit concerned that the warm air, once expelled downwards and out from the BigWater radiator, has nowhere else to go but rise back upwards into the unit.
At the rear of the BigWater 760is we find the P500 pump and reservoir, which should hold up to 130cc of coolant. The P500 uses ceramic bearings which should extend the lifespan of the pump and has a maximum pumping capacity of 500L/hr. Like everything else, it needs a 4-pin power connector to run properly, and also comes with a three-pin motherboard connector and speed control dial that will allow the user to monitor and adjust the fan speed as they like. As stated before, we would have preferred to be able to control the fan speed externally, such as lowering the fan speed during low-performance usage in order to keep noise output down. The way it stands now, you would need to open the case each time you want to change speed settings.
The entire kit contains the Thermaltake BigWater 760is with two sets of UV-reactive neon-green tubing attached to the pump, a 500cc bottle of ethylene glycol based coolant, and a plastic squirt bottle used to transfer said coolant from storage to the reservoir. Each tube is marked either "out" or "in" to prevent confusion when attaching them to the 9800 GTX+ cards, and are fitted with medical-grade "Y" splitters. While the current configuration is meant to be connected to these two cards only, the Thermaltake BigWater 760is can easily support additional cooling components, such as CPU or Northbridge water blocks. Additional units can be purchased directly through Thermaltake on their website.