Star Citizen is gradually transitioning from DirectX 11 to Vulkan, which generally provides smoother gameplay but can face challenges with GPU bottlenecks and VRAM management, leading to mixed performance results depending on hardware. While the developers plan to eventually drop DX11 support, possibly with the upcoming Planet Tech 5 update, the timing remains uncertain due to concerns about compatibility and stability for players with older or less compatible hardware.
The video discusses the current state and future prospects of Star Citizen’s graphics API support, focusing on the transition from DirectX 11 (DX11) to Vulkan. While Vulkan has been part of the game since version 4.7, performance comparisons between Vulkan and DX11 have shown mixed results. Although Vulkan generally offers smoother gameplay with better 1% percentile FPS and fewer stutters, the average FPS has often been similar or slightly lower than DX11. However, in version 4.9, Vulkan demonstrated a noticeable improvement in average FPS, suggesting that some background optimizations may have been implemented by the developers.
The presenter tested Vulkan’s performance under GPU bottleneck conditions, which is a critical scenario since Vulkan can be demanding on the GPU. Using a powerful RTX 5080 at 4K resolution, the tests showed Vulkan providing smoother frame times and better low percentile FPS, but the GPU was not fully stressed due to CPU and memory bandwidth limitations. When testing with an RTX 3080, which ran out of VRAM at medium settings, DX11 handled the VRAM limitations better than Vulkan, resulting in superior performance and less stuttering on DX11. This highlighted Vulkan’s need for more careful memory management by developers.
Lowering the graphics settings improved performance for both APIs, but Vulkan still showed some weaknesses when the GPU was heavily taxed. Testing with an AMD 9070 XT card with 16 GB of VRAM (eliminating VRAM as a bottleneck) revealed that DX11 had better average FPS, while Vulkan excelled in the worst-case frame times. This suggests that Vulkan, while smoother, may not be as efficient as DX11 under full GPU load, though the difference in average FPS was relatively small and might not be noticeable to most players.
Regarding the potential removal of DX11 support, the video references a previous statement from a developer indicating that DX11 would be dropped once Vulkan became the default API and the game’s core technology transitioned further, possibly with the upcoming Planet Tech 5 update (version 4.11). However, the exact timing is uncertain, and it may not happen immediately. The presenter notes that removing DX11 support could pose challenges for players with older or less compatible hardware, especially since some older AMD cards reportedly have issues running Vulkan due to driver conflicts and anti-cheat software interactions.
In conclusion, while Star Citizen is moving toward a Vulkan-only future, the transition is complex and carries risks. Vulkan offers smoother gameplay but can struggle under certain GPU bottlenecks and VRAM constraints compared to DX11. The developers must balance performance improvements with hardware compatibility, especially for older systems. The complete removal of DX11 support may come with future major updates like Planet Tech 5, but it remains uncertain whether this will alienate a portion of the player base who rely on DX11 for stable gameplay.