Once passed this hurdle we then found that the Eheim pump included was dead, which tarnished our opinion of the kit’s build quality. However, a replacement arrived speedily from Gainward, and all was fine from then. It’s also worth mentioning that we weren’t the first publication to test the kit that arrived initially, so to be fair to Gainward, the pump could have been damaged by the previous reviewer.
The way the Gainward CoolFX works is simple. A pump pushes water from a tank though tubing into the water block that sits over the GPU and memory. The water cools these as it passes over them and is then pumped into the radiator. This contains a large 120mm fan to cool the water down, before it is passed back to the water block.
So how do you connect all this kit up? The water tank hooks easily to the pump and then the fan has to be connected to the radiator. The water block on the card, has two connectors – an inlet and an outlet. You then attach the tubing between the pump and card and the card and radiator. These can be cut to length to fit your case, but you need to keep the tubing bend free so that the water flow is unimpeded. Take care to attach the tubing carefully and seal the connections with the supplied screws – you don’t want any water leaking onto your motherboard.
We then started to carefully fill the tank with one part coolant to three parts distilled water. Once this was full we shorted the power supply and switched it on. The pump then whirred into life and the water moved around the system. It was then just a case of refilling the tank until it remained full, which took a few minutes to do. Naturally air will get into the system, and this is removed by rotating the fan around.
It’s then worth leaving things running to check there are no leaks, before turning it all off and carefully installing it into your PC.
Once you’ve set it all up, you need to install the Gainward ExpertTool Utility in order to get to those high overclocking frequencies. ExperTool has sliders that will let you set the GPU all the way up to 500MHz and the memory up to 1500MHz. However, even with the water cooling the Gainward can’t achieve these speeds. Instead, there are standard and enhanced modes. Standard will set the card to run at 400/1100 for GPU/memory speeds, while enhanced increases this to 450/1200. We ran all the tests at enhanced mode but to see how far we could push the card we then ran them all at 485/1400MHz. This proved to be no problem for the Gainward, with the pump keeping the system cool at all times. Therefore, its these scores that we’ll be quoting.
Comparisons with an air cooled GeForce 6800 Ultra depend on which board you look at. The nominal specifications for the 6800 Ultra are 400MHz for the GPU and 1,000MHz for the memory. However, the XFX 6800 Ultra card we looked at ran at 450MHz, while the AOpen Aeolus 6800 Ultra that we’ll be reviewing soon only runs at 400/1100.