AMD Radeon RX 470 Review: Polaris Gets Even More Affordable
RX 470 Overclocking, Power Consumption, Noise, and Temps
We also spent a little time overlcocking the new ASUS Radeon RX 470 STRIX, to see what kind of additional performance we could squeeze out of it. Before we get to our results, we should talk about updates to AMD's Radeon Software Crimson Edition driver suite for Polaris GPUs that enable a host of previously unavailable overclocking features. With the update, the Overdrive tab is gone in favor of a new one called WattMan. WattMan arrived with the release of the Radeon RX 480 a few weeks back.
Like previous-gen Radeon cards, when turbo boosting, frequencies and voltages scale upwards -- power and temperature permitting -- based on the GPU's workload at the time. With Overdrive, you could overclock using a fixed percentage frequency offset and bump up the GPU power curve manually. But with WattMan, while similar tools are still available, users also have the ability to alter frequencies and voltages on a per-voltage step (or state) basis.
WattMan Running On The Radeon RX 470
With WattMan, users can also tune fan speeds, memory clocks, voltages and the power limit. There's a real-time graph at the top that maps out GPU activity, clocks, and temperatures as well, along with the memory clock and fan speed over time.
To overclock the Radeon RX 470, we took a straightforward approach. We upped the power and temperature targets, while also bumping up the fan speed curve and increasing the low acoustic limit. Changing these settings allows the cooler to dissipate more heat at any given voltage point, while also allowing the GPU to boost longer and use more power. While we had the card overclocked, we re-ran a couple of tests and saw some nice improvements in performance in the games / settings we used. Thief showed a nice jump in performance, as did 3DMark as you can see...
Ultimately, the GPU peaked at only 1270MHz, but by upping the power limit and tweaking the fan speed, the overall performance of the card increased quite a bit. We should also note that the GPU temperature remained below 70 degrees C, though we had the fan speed cranked up pretty high. Dropping the fan speed to a lower, and hence quieter, speed would have resulted in higher GPU temps. The overclock allowed the Radeon RX 470 card to overtake the GTX 970 in these tests, so there are some good gains available with minimal tinkering.
There is quite a bit to see in this graph. Speaking in absolutes, the Radeon RX 470 consumed about the same amount of power as the GeForce GTX 970, and markedly less than the RX 480. In total, the RX 470 used about 6% less power than the RX 470, but performance was about 10 - 15% behind its big brother, give or take a couple of points depending on the settings used. That means the RX 470 is somewhat less efficient than the RX 480, though power may shake out differently with a board from a different AMD OEM partner.
Noise is a non-issue with the ASUS Radeon RX 470 STRIX we tested. When idling, the card is inaudible over the other components in our test system (we test inside a mid-tower chassis with a Corsair HX series PSU and Arctic Cooling CPU air-cooler on the CPU). Under load, the fans do kick up a touch, but the card remains relatively quiet overall.