Elden Ring may have a strange relationship with non-standard aspect ratios on PC, as it turns out. Though none of FromSoftware's previous PC releases have offered support for high frame rates and ultra-wide resolution standards in an official capacity, some ultra-wide monitor users have noticed strange behavior when first loading the game.
As originally reported on the ultrawidemasterrace subreddit by Ewoek, Elden Ring seems to occasionally load in proper 32:9 aspect ratio on the first startup, only for the black bars to limit the used screen real-estate about 30 seconds afterward. This claim was further corroborated by a number of other users, suggesting that there's more to the game's lack of ultra-wide aspect ratio support than it might first seem.
Elden Ring is Steam Deck Verified
Though the fact that Elden Ring has strange performance issues on all platforms has already been criticized by the game's player base, less attention has been given to the fact that the game offers no apparent support for ultra-wide resolution standards by default, specifically 21:9 and 32:9 aspect ratios. This is standard fare for FromSoftware games that usually gets fixed via community mods, but it now seems that there is some sort of ultra-wide support coded into Elden Ring after all.
While Elden Ring patch 1.02 may have resolved some outstanding technical issues with the game, the idea that the game would deliberately block out non-standard aspect ratios seems rather strange. At face value, the only reasonable assumption is that FromSoftware may have planned to include proper 21:9 and 32:9 support at some point, only to come across issues that couldn't be resolved before launch.
Further underlining Ewoek and other r/ultrawidemasterrace
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