Of the eleven games tested five of them showed absolutely no change in performance regardless of the quality settings, and those games included Crysis 3, Battlefield 4, The Witcher 3, Dragon Age: Inquisition and Dying Light.
There are some seriously good looking and very demanding games in that list.
Crysis 3 only used 2.4GB of VRAM and yet both the GTX 960 and R9 380 struggled to deliver playable performance using the best graphics settings at 1080p. A similar story was found when testing with The Witcher 3 and Dragon Age: Inquisition. Interestingly, Dying Light consumed up to 3.5GBs of VRAM when there was enough at its disposal and yet there was no performance difference between 2GB and 4GB graphics cards.
Then we ran into games such as Assassin's Creed Syndicate and Just Cause 3, where the 4GB models did provide additional performance, but only when faced with unplayable conditions. For example, Assassin's Creed Syndicate at 1080p using the R9 380 and GTX 960 on "Ultra High" settings, frame rates went from the low 20s on 2GB models to high 20s for the 4GB models.
Once the graphics settings were set back to "High" both the 2GB and 4GB models provided very playable performance and the GTX 960 delivered the exact same performance regardless of memory capacity.
The only games that genuinely benefited from having a larger 4GB frame buffer were Star Wars Battlefront, Shadow of Mordor (if only slightly) and Rainbow Six Siege. Of those games, Rainbow Six Siege was the big one, and while the 2GB R9 380 and 2GB GTX 960 still delivered very playable performance at 1080p using maxed out settings, the 4GB models were much faster. The 4GB 39 380 enjoyed 23% more performance, while the GTX 960 was 16% faster.
This was a common theme and we found that while the R9 380 benefited from the larger 4GB frame buffer in games such as Grand Theft Auto V, Just Cause 3 and Star Wars Battlefront, the GeForce GTX 960 didn’t. In fact, we saw very few cases were the GTX 960 4GB made sense, and certainly there were no instances where the 2GB frame buffer crippled performance.
