GeForce GTX 275 and Radeon HD 4890 Round-Up

We'd like to cover a few final data points before bringing this article to a close. Throughout all of our benchmarking and testing, we monitored how much power our test systems were consuming using a power meter. Our goal was to give you an idea as to how much power each configuration used while idling and under a heavy workload. Please keep in mind that we were testing total system power consumption at the outlet here, not just the power being drawn by the motherboards alone.

When equipped with a GeForce GTX 275, our system pulled down from 155W to 164W at idle, and then almost double that when under load conditions.  Installing any of the Radeons upped the idle draw to 194W, nearly 30-40W more than the GeForce GTX 275.  Under a full load, however, the total draw was typically slightly less than the GTX 275.

Since we're on the subject of power consumption, which is related to heat, we also made note of the minimum and maximum temperatures recorded by the GPU sensor using HWMonitor.  In general, we saw that the HD 4890s were running nearly 25% hotter than the GTX 275 at idle, but the Radeons were actually somewhat cooler than the GTX 275s under load.  As the majority of the cards are using stock cooling methods, it makes sense that the temperatures are, for the most part, similar save for the MSI GTX 275 Twin Frozr OC.  The twin-fanned cooler used on MSI's card shaved off a few degrees at idle, but did a great job at load, resulting in temps that, like the Radeons, were significantly lower than stock cooled models.