How to improve FPS in Subnautica 2 (PC)
Subnautica 2 is an Early Access title (May 2026), so this guide relies on the official Steam requirements, the documented behavior of Unreal Engine 5 (the game switched from Unity to UE5 compared to the first entry), and early community impressions. There isn't yet a consolidated benchmark database like games with years of history have, so treat the percentages in this guide as reasonable estimates, not lab-measured figures. We'll keep updating the guide as more data emerges during Early Access.
This is what you'd gain with a NVIDIA RTX 3060
Want the RTX 3060 at the best price?
Check the current price on Amazon.
Calculations based on our FPS model combined with the % gain of each setting (measured in public benchmarks).
1. Quick wins (no visual loss)
Start here. Each one adds a little, but together they give +48% free FPS.
Cap the frame rate at 60 FPS (or your refresh rate)
In the current Early Access state, an uncapped frame rate generates noticeable micro-stutter from irregularly offloading the CPU/GPU. Setting a stable cap reduces frametime spikes even if the average FPS doesn't rise much.
Lower Global Illumination (Lumen) from Epic to High/Medium
Lumen's dynamic global illumination is one of the most expensive systems in UE5. Dropping it from Epic to High keeps most of the underwater atmosphere (which depends heavily on light) while freeing up a notable percentage of GPU.
Reduce Shadows by one or two levels
Dynamic shadows in UE5 have a high cost for a moderate visual impact underwater, where light diffusion already softens most contours a lot. It's one of the first settings to touch according to early community testing.
Enable upscaling (DLSS/FSR/TSR) in Quality mode
The game natively includes upscaling from its Early Access launch. In Quality mode the loss of sharpness is hard to notice in motion and compensates well for the cost of Lumen and Nanite.
2. Medium impact settings
Here's where most of the FPS is. Minor visual impact, major performance impact.
Lower View Distance
Since this is an underwater open world with continuous geometry streaming, view distance directly affects how much chunk loading and detail the engine has to manage at any given moment. Lowering it helps especially in open-sea areas.
Adjust Shading and Effects (particles, suspended matter)
Suspended particles and water refraction/caustics effects look great but are expensive. Dropping one notch reduces load without losing the feeling of being underwater.
Reduce real-time Reflections quality
Water surface and metallic base object reflections use Lumen's software-based tracing, at a high cost. Switching to a lighter mode keeps reflections believable at a much lower GPU cost, especially at the surface.
Restart the game every few hours during long sessions
Several community reports point to FPS degradation and rising RAM usage after long sessions, consistent with a known memory leak in this Early Access build. Restarting the process restores initial performance until a patch arrives.
3. Upscaling (DLSS / FSR / XeSS)
The biggest gain in the game. Compatible with almost any modern GPU.
DLSS (NVIDIA, Quality mode)
+25% FPSNatively supported since Early Access launch. It's the recommended option on NVIDIA RTX GPUs; in Quality mode the sharpness difference versus native is minimal and compensates well for the cost of Lumen.
FSR (AMD and non-NVIDIA GPUs, Quality mode)
+20% FPSA cross-platform alternative for AMD GPUs or older NVIDIA cards without tensor cores. Works well in Quality mode; in Balanced or Performance mode the 'ghosting' effect on water is somewhat more noticeable than with DLSS.
TSR (Unreal Engine 5's native upscaling)
+15% FPSA fallback solution built into the engine itself, useful if DLSS/FSR cause issues or on Intel hardware. Offers less of a gain than DLSS but is stable and doesn't depend on external drivers.
4. Tips by GPU
NVIDIA
- •Enable DLSS in Quality mode as your first option before touching other settings.
- •On 40-series GPUs, try DLSS 3 Frame Generation to smooth out frametime in the heaviest streaming zones.
- •Keep Game Ready drivers updated: on recent UE5 games, the first months of Early Access usually bring several driver optimizations.
AMD
- •Use FSR in Quality mode as a practical equivalent to DLSS for your tier.
- •If you have an RX 6700 XT or better (the official recommended spec), you should comfortably run 1440p Medium with FSR Quality.
- •Check Adrenalin for a Subnautica 2-specific profile; recently released UE5 games usually get quick compatibility tweaks.
Sistema
- •Meet at least the officially recommended 16GB of RAM; with 12GB (the minimum) you're more likely to notice the memory leak in long sessions.
- •Install the game on an SSD: continuous underwater open-world streaming hits much harder on an HDD than in most games.
- •Close overlays and background recorders during your first hour of play, when UE5's shader compilation is already using CPU/GPU intensively.
5. Known game issues
Shader compilation stutter when entering new biomes
As in most Unreal Engine 5 games, the first 30-60 minutes of play show micro-pauses whenever a new material, creature, or light effect appears, because the engine compiles the shader on the fly. Once compiled it stays cached and the stutter disappears on later visits to the same biome.
Performance degradation in long sessions (possible memory leak)
Several players report FPS drops and increased stuttering after 3-4 hours of continuous play, consistent with growing RAM usage that isn't properly released. It's a typical Early Access build issue; restarting the game restores performance until a patch is released.
6. Frequently asked questions
Why does Subnautica 2 have such low minimum GPU requirements (GTX 1660) if it uses Unreal Engine 5?▾
Is it worth enabling co-op mode if my PC is already at its limit?▾
Which upscaling technology should I use if I have an AMD GPU?▾
Is this guide final?▾
Want to know exactly how many FPS YOUR PC will get?
Enter your GPU and CPU in our calculator and measure the real impact of each setting.
Calculate FPS for Subnautica 2 →Calculations based on consensus of technical sources and our own FPS model. More about our methodology →