ASUS EN8800 GTX AquaTank

While ASUS is well known among hardware enthusiasts for their high-end motherboards, they’ve also quietly produced some of the most innovative graphics cards we’ve tested. For instance, ASUS’s Extreme Radeon X1800 XT TOP/2DHTV and Extreme N7800 GTX TOP both took home awards from us in 2005 and 2006. These cards fused Radeon and GeForce GPUs with aftermarket cooling units from the cooling aficionados at Arctic Cooling as well as overclocked graphics core and memory speeds to deliver enhanced performance. In more recent weeks, ASUS has reintroduced one of our favorite programs, the ASUS Smart Doctor, for their GeForce 8500 GT and 8600 GT cards. If you recall, ASUS’s Smart Doctor software was the first utility to combine GPU overclocking and hardware monitoring all in one software package. Smart Doctor could even dynamically adjust the clock speed of the GPU based on usage or temperature!

With their latest Smart Doctor software, ASUS provides the ability to adjust the clock speed of the stream processors. Previously the clock speed of the stream processors was tied to GPU’s core clock speed – overclocking the graphics core of the GPU also overclocked the stream processors by a fixed ratio. NVIDIA promised they would add the ability to clock the stream processors independent of the graphics core into nTune, but so far this feature hasn’t surfaced. This gives ASUS a bit of an exclusive for the time being (the latest build of RivaTuner also supports independent clock speed adjustment for the stream processors as well).

ASUS’s EN8800 GTX AquaTank is quite unique. In a GTX market where practically everyone is using the same NVIDIA board design and cooling, the EN8800 GTX AquaTank really stands out!


ASUS has partnered with Thermaltake to produce the EN8800 GTX AquaTank. The card uses Thermaltake’s popular Tide Water liquid cooler to help keep the GPU cool. Inside the Tide Water cooler lies an all-copper radiator, water reservoir, 12V pump, and finally, a fan for supplying fresh air to the whole setup. So how does it all work?

The GeForce 8800 GPU is supplied with fresh, coolant water from one of the Tide Water’s two hoses. This coolant is directly responsible for cooling the GPU. This heated coolant is then passed back to the external Tide Water cooling enclosure (via the second rubber hose) where it’s cooled and then passed back to the GPU. This cycle is constantly running in motion, working to keep the graphics core cool. The 12V pump at the back of the Tide Water unit is responsible for keeping the coolant in motion, while the radiator works to keep the coolant cool. Heat from the coolant is transferred to the air via a radiator at the front of the Tide Water unit. The radiator is a large, all-copper unit, and is composed of numerous thin fins to increase its surface area. Finally, to help keep the radiator cool, a fan is used to pass fresh cool air from within your PC’s case over the radiator and its fins before the air exhausts outside your system’s case at the end of the card. The fan’s RPMs can be adjusted via a switch on the Tide Water cooling unit, two different modes are provided a “High” setting, and a “Low” setting.



The TideWater unit is good for 10,000 hours before its reservoir needs to be refilled with coolant. The back of the Tide Water cooler has a water line (next to the fill port), so you can keep track of once the reservoir needs to be refilled. A Molex connector is located on the back of the Tide Water unit in order to supply power to the Tide Water’s pump and fan.

The Tide Water cooling unit is quite large and will take up two slots within your case. Fortunately the hoses are long enough that you can place the Tide Water wherever you’d like: you don’t have to place it in the slots directly adjacent to your graphics card.

But the ASUS EN8800 GTX AquaTank is much more than just a GeForce 8800 GTX with a Tide Water unit installed. Besides the Tide Water cooling unit, you’ll also no doubt notice the heatsink/fan unit on the 8800 GTX card itself. ASUS actually goes one step beyond your typical Tide Water installation with this step.

The fan provides cool air to the copper water block itself, as well as the black aluminum heatsink which is responsible for keeping the board’s memory modules and power circuitry cool. Air from this fan is ducted, passing over the VRM, memory modules, and the G80’s external video chip, and then exits out the left side of the duct. It’s important to note that this hot air is not exhausted out the back of the case. The duct essentially stops short, it doesn’t extend all the way to the grille on the back plate of the graphics card. We should also note that this duct is tall enough to swallow the slot directly next to your graphics card, so this unit is a dual-slot cooler. The fan on the graphics card doesn’t draw power from the board, instead it has its own Molex connector. You’ll want to plug this Molex connector into the Tide Water Molex power connector, and then from there you’ll need a Molex from your system power supply to power both fans (if you don’t want to plug in the fan above the GPU, the ASUS card still functions fine although obviously it will run a little warmer). All told, the EN8800 GTX AquaTank will consume 4 slots total to fit within a case.

In use, the AquaTank system works quite well. We recorded the following temps (in degrees Celsius) with the ASUS AquaTank versus the XFX XXX, which is also factory overclocked:

GPU Temps
Card	Idle Temp	Load Temp
ASUS EN8800 GTX AquaTank (High fan setting)	56	70
ASUS EN8800 GTX AquaTank (Low fan setting)	66	81
XFX GeForce 8800 GTX XXX Edition	58	78

All this cooling does come at a downside though: noise. At the “high” fan setting, the AquaTank generates 60 decibels of noise, and even at the stock “low” setting, the card is louder than any other GeForce 8800 GTX we’ve tested at 48 decibels. It isn’t unbearably loud considering the card has two fans, but it is noticeable nonetheless.

Besides its unique cooling, the other aspect of the AquaTank that stands out is its clock speeds. ASUS runs the board at 630MHz core/1458MHz shaders and 2.06GHz memory. This makes it the fastest card in this roundup, and one of the fastest GTX cards on the market.