Multi-GPU Results: Tomb Raider
A pair of GeForce GTX 770s lands between the 780s and AMD’s Radeon HD 7990. Though, when it comes to average frame rates, the 770s, 7990, and GeForce GTX 680s are all pretty much identical.
When we spread frame rates out over time, the second-to-last-place GeForce GTX 690 actually appears more consistent than the Radeon HD 7990, which spikes as high as 110 FPS, but then drops as low as 20. The GeForce GTX 770s we’re benchmarking today peak just north of 100 FPS and don’t drop any lower than 40, yielding what I’d consider to be a superior experience that should reflect in the frame time variance numbers.
And there’s the smoking gun. The variance you experience between the time it takes to render one frame and then the next does matter, as we all know. Two GeForce GTX 770s, at worst, are in the 2 ms range of difference. The pace between frames is even, so even when frame rate drops, frames are being delivered at a consistent interval. The Radeon HD 7990’s average is higher at 2.2 ms, and at worst, variance spikes at almost 20 ms.