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Cooling System

The cooling system of the GeForce GTX 295 is similar to the one installed on the GeForce 9800 GX2. Besides performing its main function, it also serves as the foundation for the whole graphics card because both PCBs are fastened on it. >From a technical point of view, the cooler is like a dual-sided sandwich with copper heat-exchangers on the exterior sides for cooling the GPUs and with protrusions for cooling other components. Inside the cooler there is a thin-ribbed aluminum heatsink connected to the heat-exchangers with flat heat pipes.

We did not risk taking the cooler apart because its parts were fastened with thermal glue, but the photographs show the cooler’s key features anyway. The heatsink ribs are placed at an angle to the mounting bracket, so only some of the hot air leaves the system case through the slits in the bracket whereas the other portion of the air goes into the system case through a hole in the casing. However, the share of the exhausted air is far higher in comparison with the GeForce 9800 GX2. 

As we noted above, the cooler’s aluminum bases have a number of protrusions for establishing thermal contact with the memory and NVIO chips as well as with the power elements of the GPU voltage regulators. Nvidia’s traditional fiber pads soaked in white thermal grease are used as a thermal interface for the memory and NVIO chips. A very dense gray thermoplastic material is used for the power components. Besides the two main heat-exchangers responsible for the GPUs, there is a third and smaller one, responsible for the PCI Express switch. Dark-gray dense thermal grease is employed as a thermal interface – you can see it in many modern graphics cards.

A 5.76W blower is installed at the back of the “sandwich” for blowing through the heatsink. It is connected to the top PCB with a 4-pin connector. The blower gets fresh air from above and below the card through the holes in the PCBs. Each PCB is secured on the cooler’s base with 13 spring-loaded screws. The cooler is covered from the top with a metallic casing that has a rubberized coating. At the bottom there is just a plastic plate with an EVGA logo that covers the ferrite cores of the chokes of the voltage regulator.

This design can hardly be called optimal considering that the GeForce GTX 295 is going to dissipate about 220-240 watts of heat. However, this cooler and the graphics card at large is a compromise the developer had to concede in order to stay within the required dimensions. The cooler seems to be able to cope with its job, but we don’t expect it to be exceptional in terms of cooling performance or noise parameters. We will check this out in the next section, though.

 
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