How Microsoft Created Its New Xbox FPS Boost Feature
Through a little bit of hardware wizardry, Microsoft found a way to double the frame rate on various backwards compatible games.
Backwards compatibility has been a big draw for Xbox, and with the addition of new features on the Xbox Series X/S consoles, those legacy titles are about to look and run better than ever before. This week saw the reveal of Xbox FPS Boost, a new upgrade for specific games that almost doubles their frame rates and will be introduced soon to Sniper Elite 4, Far Cry 4, Watch Dogs 2, UFC 4, and New Super Lucky's Tale.
So how did Microsoft engineer this feature for its library of backwards compatible games? By examining how these games were originally written and how their internal clocks were managed.
"When we developed the technique, the first thing we did was look across the catalog and said 'What games do we believe that we can actually make this technique work for?'," Xbox program management director Jason Ronald explained on the Colt Eastwood YouTube channel. "We identified a large set of games, and then we started testing the games to make sure the games actually play as good as they should. In some cases, there were some games that we had on the list that we discovered would play great but occasionally we'd see animations run twice as fast, or maybe the engine was running so fast that it would break gameplay."
Ronald explained that the Xbox team had discovered that the CPU and GPU on the Xbox Series X/S consoles were entering an idle state when running older games because they'd complete their tasks quickly, and so the team came up with a method that used the spare power of the next-gen consoles to increase the frame rate of games.
At the platform layer, the Xbox Series X/S fakes the title out so that it doesn't know that the frame rate has been increased. The image rendered is only on the screen for a fraction of a second, and then the title starts processing the next frame immediately after to achieve the boost.
Aside from technical issues in certain games where the technique ran too well, one other hurdle that Xbox has had to deal with is publisher approval. Every game tested for Xbox FPS Boost also has to be considered on artistic terms as some titles were designed with a specific frame rate in mind. Xbox will only a game to use FPS Boost if it and the game's publisher sign off on it, as some games may be in line for a future remaster and this feature could interfere with those plans.
Ronald added that after the initial batch of games released this month, new games with Xbox FPS Boost will arrive every couple of weeks over the next couple of months. A future update will also allow players to toggle both Auto HDR and Xbox FPS Boost on or off, in case users wish to play a game in its original state without any enhancements.