Results: Ashes, BF1 & Destiny 2
In some games, we noticed that Sapphire's Radeon RX Vega 64 Nitro+ was actually slower than AMD's reference Vega 64 card, even though its clock rates are higher. This is not a testing error, nor a specific problem with the model we're testing. Other partner cards have been observed to suffer the same issue, with performance varying based on driver version.
Since this did not occur in all games, or to the same extent, we are guessing that optimizations made in AMD's driver since Vega 64's launch do not apply to third-party cards, since they're not explicitly treated as RX Vega in the driver. It's almost like there's a Radeon fall-back mode. Hopefully the company solves this issue sooner than later. Until then, just know our test results are correct, and there are times when Sapphire's Nitro+ board under-performs the AMD model.
Ashes of the Singularity: Escalation (DirectX 12) @ 2560x1440
Case in point. The Radeon RX Vega 64 Nitro+ with AMD's new Adrenalin Edition driver lands well behind our reference board running 17.10.3, despite a higher GPU frequency and lower temperature.
Ashes of the Singularity: Escalation (DirectX 12) @ 3840x2160
Radeon RX Vega 64 enjoys a major memory bandwidth advantage, which undoubtedly helps carve out a small lead over GeForce GTX 1070 Ti and 1080 at 3840x2160. After all, those Nvidia cards achieve similar frame rates, despite their dissimilar memory technologies. Unfortunately, Sapphire's card trails both, losing big to AMD's reference Radeon RX Vega 64.
Battlefield 1 (DirectX 12) @ 2560x1440
The performance picture looks a lot better in Battlefield 1, where Sapphire's card benefits from a higher clock rate than AMD's reference Radeon RX Vega 64, just as we'd expect.
Battlefield 1 (DirectX 12) @ 3840x2160
The same goes for 3840x2160, where the Radeon RX Vega 64 Nitro+ lands closer to GeForce GTX 1080 Ti than Nvidia's vanilla GeForce GTX 1080.
Destiny 2 (DirectX 11) @ 2560x1440
Sapphire also carves out a nice win against AMD's Radeon RX Vega 64 reference card in Destiny 2.
Destiny 2 (DirectX 11) @ 3840x2160
Sapphire keeps its momentum going at 4K, where the Nitro+ card beats the reference Radeon RX Vega 64.
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