BFG's GTX 295 H2OC: Water-Cooled Graphics

by Joel Hruska — Monday, September 21, 2009, 10:30 AM EDT

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Thermal Analysis

Normally when we gather GPU temperature data, we log the results from an open-air testbed and leave it at that. There are far too many cases and ambient temperature conditions out there in the real world to possibly model. In the case of the BFG H₂OC, however, there was good reason to put it into an enclosure. Without actually testing the card in a restricted environment against an air-cooled model, there was no way to compare the real advantage of water over air.

We've got a roomy Cosmos case that we figured would be just the thing for a watercooled card like the H₂OC, and did not expect any problems until we saw BFG's image of the card in a case. See if you can spot the problem:

While it's true that the entire point of this video card is to appeal to customers who don't already have a water-cooled rig, BFG's use of a stock Intel cooler, combined with the warning on the back of the box, raises compatibility concerns. Enthusiast systems, whether OEM-built or otherwise, tend to use third-party heatsinks, most of which are significantly larger than Intel's own reference design. This point was driven home with particular strength when we realized the CPU cooler inside our Cosmos testbed was far too large to give the H₂OC's radiator+fan design sufficient clearance. De-coupling fan and radiator and reattaching through the 120mm fan grate would've been the simplest way to fix the problem, but the radiator fan is actually pop-riveted in place.

Thermal Analysis

GPU Temperature Data

Here's our starting point; a base comparison of GPU temperatures using the air-cooled GTX 295, the water-cooled BFG H2OC at low fan speeds, and the same card at its medium fan speed. While we could have modeled the card at maximum RPM, there's no reason to buy an $800+ card if you want the sound of an air turbine—you can literally buy that at half the price. One thing to remember here is that the air-cooled card was perfectly stable at all temperatures, despite the sky-high readings. Water is an easy winner, here, by a sizable margin.