by Rob Williams on February 21, 2011 in AMD-Based GPU
Sapphire’s Vapor-X series of graphics cards have long been praised for their ability to deliver superb cooling with the help of an efficient cooler, and not surprisingly, the HD 6800 series isn’t without such a model. We’re taking a look at the company’s Radeon HD 6870 1GB variant, and see if its $10 price premium is worthy.
To test our graphics cards for both temperatures and power consumption, we utilize OCCT for the stress-testing, GPU-Z for the temperature monitoring, and a Kill-a-Watt for power monitoring. The Kill-a-Watt is plugged into its own socket, with only the PC connect to it.
As per our guidelines when benchmarking with Windows, when the room temperature is stable (and reasonable), the test machine is boot up and left to sit at the desktop until things are completely idle. Because we are running such a highly optimized PC, this normally takes one or two minutes. Once things are good to go, the idle wattage is noted, GPU-Z is started up to begin monitoring card temperatures, and OCCT is set up to begin stress-testing.
To push the cards we test to their absolute limit, we use OCCT in full-screen 2560×1600 mode, and allow it to run for 15 minutes, which includes a one minute lull at the start, and a four minute lull at the end. After about 5 minutes, we begin to monitor our Kill-a-Watt to record the max wattage.
In the case of dual-GPU configurations, we measure the temperature of the top graphics card, as in our tests, it’s usually the one to get the hottest. This could depend on GPU cooler design, however.
Note: Due to power-related changes NVIDIA made with the GTX 580 & GTX 570, we couldn’t run OCCT on that GPU. Rather, we had to use a run of the less-strenuous Heaven benchmark.
Oddly, the idle wattage on Sapphire’s card is a bit higher than our reference, but the load wattage shaves 6W off. For temperatures, Sapphire’s card clearly dominates, proving to be our coolest card at max load than anything else in our line-up.