Power draw, thermals, and noise
We test power draw by looping the F1 2020 benchmark at 4K for about 20 minutes after we’ve benchmarked everything else and noting the highest reading on our Watts Up Pro meter, which measures the power consumption of our entire test system. The initial part of the race, where all competing cars are onscreen simultaneously, tends to be the most demanding portion.
This isn’t a worst-case test; we removed the Core i7 8700K’s overclock and specifically chose a GPU-bound game running at a GPU-bound resolution to gauge performance when the graphics card is sweating hard. If you’re playing a game that also hammers the CPU, you could see higher overall system power draws. Consider yourself warned.
You can see the improved efficiency of the RDNA 2 architecture in the Radeon RX 6800 XT’s results. Despite trading blows with the RTX 3080 at 4K and often beating it outright at 1440p gaming, AMD’s card uses less power than its rival. The step-down Radeon RX 6800 is flat-out more powerful than the RTX 3070, so it's no surprise to see it draw slightly more power than the GeForce card. That said, the RX 6800 barely uses more power than the RTX 3070 and also packs in twice as much RAM. It’s a good showing for AMD.
We test thermals by leaving GPU-Z open during the F1 2020 power draw test, noting the highest maximum temperature at the end.
AMD’s switch to axial cooling delivers solid results, and a tremendous improvement over previous Radeon reference boards. The ultra-powerful Radeon RX 6800 XT maxed out at 76 degrees Celsius in our system, a whopping 10 degrees below what the blower-style cooler on the last-gen Radeon RX 5700 XT hits—and that was a midrange GPU.
Nvidia’s radical “flow-through” cooling system with its whole-chassis heat sink helps the RTX 30-series Founders Edition cards run much more quietly than AMD’s Radeon RX 6800-series options. The Radeon RX 6800 and 6800 XT nevertheless achieve perfectly acceptable noise levels, unlike the blower coolers of old. You’ll hear these cards when you’re gaming, yes—there’s still room for AMD’s custom board partners to innovate here—but not anywhere near annoying levels. The Radeon RX 6800 XT is louder than the 6800 despite its extra half-slot of heatsink capacity, and our model exhibited faint coil whine when it hit especially high frame rates in Strange Brigade and Rainbow Six Siege. That can happen to any individual card, and we only noticed it only when the 6800 XT was pumping out several hundred frames per second.
Bottom line? These are good coolers, with nothing to complain about—something you couldn’t say about AMD reference boards in the past.
Next page: Should you buy the Radeon RX 6800 and 6800 XT?