YouTuber RandomGamingInHD (@RGinHD on Twitter) recently published a video on the platform discussing the image improvements in older titles, such as GTA IV, The Elder Souls: Oblivion, and The Witcher 3 with the graphics card the Intel Arc A750 using a Vulkan-based translation layer inside of DirectX environments, especially DirectX 9 to DirectX 11, called DXVK.
Intel Arc A-series Graphics Cards + Vulkan = increased performance in older gaming titles
Linux offers Vulkan many support languages, including older architectures and technologies that mainline Windows support would not provide. RandomGaminginHD discovered that, in DirectX 9 games, the system would, rather than use the enhancement of the software, filter the graphics through emulated layers because of the lack of further support. He notes in the video below the instructions on how to implement Vulkan support for DirectX, as well as examples from the games listed above.
The official wiki for DXVK states that the translation layer based on Vulkan can be used on DirectX 9, DirectX 10, DirectX 11, and Linux with Wine and offers support for Steam Deck.
In GTA IV, he noticed that the highest frame rates with the Intel Arc A750 graphics card, on average, were slightly under 60fps. Still, when implementing the files to utilize Vulkan, the framerate increased to 123fps on average. When doing the same test in The Elder Scrolls: Oblivion, DirectX 9 averaged 200fps.
Lastly, in The Witcher 3 (please remember that this is the original Witcher 3 game and not the remastered version), he stated that two different files needed to be implemented due to the game running on DirectX 11. When changing to Vulkan, the frames per second decreased instead of improving the game. In Vulkan, RandomGaminginHD noticed a drop of 4 frames on average per second compared to DirectX 11. He also felt that the game played better on the Vulkan "DXVK" driver and was less conflicting than in DirectX 11.
The performance gain is impressive between the two Intel graphics drivers. The interest in maintaining original games, either through normal graphical means or with the recent RTX enhancement made to the game Quake II, is fascinating. With open-source resources, like DXVK, available to users, it may push developers to offer newer support for additional legacy PC titles.
He also notes that in using the files from the DXVK driver, you may run the risk of altering the game and could receive a ban if playing a multiplayer game with the enhancement and suggests only doing this at your own risk (and in single player titles only).