Let's take a look at how much juice the GTX 1070 needs to do its thing. Our "under load" tests aren't conducted in an absolute peak scenario. Instead, we have the cards running a real game, Crysis 3, in order to show us power draw with a more typical workload.
At idle, our test system consumes a few more watts with the overclocked GTX 1070 inside than it does with the stock-clocked GTX 1080 Founders Edition. That shouldn't come as any surprise.
Loading the GTX 1070 up with Crysis 3 brings our system power draw within 10 watts of the GTX 1080 FE. Impressively, we can see that the GTX 1070 delivers GTX 980 Ti-class performance while allowing our test system to draw 27% less power under load. Process shrinks are a wonderful thing.
At idle, all of our cards except the GTX 1080 stop their fans, so the noise floor of our lab is the limitation of our measurement. Under load, however, the GTX 1070 Gaming Z card produces noise levels bested only by the Radeon R9 Fury X's closed-loop liquid cooler. MSI's GeForce GTX 980 Ti was already among the quietest cards of that type we've tested, so it's good to see the company continuing its commitment to quiet gaming.
Most importantly, the sound from MSI's cooler is also a pleasant, broad-spectrum one. Even when we pushed them to full blast for the heck of it, the twin fans didn't lose their polite character. Overall, MSI deserves high praise for the noise, vibration, and harshness characteristics of its latest cooler.
Of course, quiet computing is just one of the things a good graphics-card heatsink needs to deliver. The Radeon R9 Fury X and its liquid cooler aside, the GTX 1070 Gaming Z is only bested by the much louder and more aggressive cooler on the Gigabyte GTX 980 Windforce card. While it's not an entirely fair comparison, it's clear from these results just how much of a drop in temperatures one can get from a custom card compared to Nvidia's reference design, too. The Founders Edition GTX 1080 runs a full 15° C hotter than the GTX 1070 Gaming Z, even if that card does have the benefit of exhausting hot air directly from the case. We may have to see how MSI's cooler performs atop a fully-enabled GP104 chip at some point.