Results: Metro Last Light And Bioshock Infinite
Metro Last Light
Let’s take a look at a classic game that's so demanding we can't help but retain it as a benchmark. Nvidia’s GeForce GTX 980 comes out ahead in Metro Last Light across all resolutions, including UHD. The Radeon R9 Nano’s performance might not be good enough for a win, but it is ample for playable frame rates at 3840x2160.
Nvidia's GeForce GTX 970 Mini does surprisingly well, beating a factory-overclocked Radeon R9 390X all the way to our highest test resolution. This came as a surprise to us. Old though it may be, Metro just isn't well-optimized on AMD's hardware, it seems. At least the performance we're reporting is playable.
The Radeon R9 Nano’s anything-but-smooth (red) curve at Ultra HD shows the strict power consumption limit in action. AMD's limit results in a varying clock rate, which keeps the card from doing better in this benchmark. The results are still alright, especially when you consider the card's low power consumption.
Normalization via the frame time averages doesn’t really show anything new. The different frame render times attributable to a constantly changing core frequency are easy to spot.
The last graph gives us the bottom line: neither AMD's Radeon R9 Nano nor any other graphics card encounter extreme spikes. They all stay below a calm 5ms of variance between any two frames.
It’s striking that the factory-overclocked GeForce GTX 980 dominates the Radeon R9 Nano across all resolutions. Even Nvidia’s smaller GeForce 970 Mini (OC) with its 3.5GB of usable graphics memory scores points by leading the Radeon R9 390X and its 8GB of GDDR5 across each resolution, including Ultra HD. By the way, all of the graphics cards we're testing provide playable frame rates at 4K. This is an uncommon and certainly welcome sight.
The frame render times don’t show AMD or Nvidia pulling ahead, so the competition ends up fairly balanced. The only exception is AMD's Radeon R9 390X, which shows more spikes overall and gets worse as resolution increases.
After normalizing the graph with the help of each card’s average frame time, the above observation becomes even easier to see. AMD's boards are worse when it comes to frame render time variance, but the Radeon R9 390X is the only card to do badly enough for it to be perceivable during gameplay.
Our smoothness analysis confirms these findings as well. The Radeon R9 390X’s performance is worse in the middle of the benchmark. The culprit is found in the high overclock all the way to 1100MHz. If the clock rate is set to 1000MHz, then frame time variance decreases significantly. We reproduced this behavior in the lab.