Rust

CPU Role — cores, clocks, and how they relate to this game's results

The AMD Ryzen 5 8400F is a 6-core, 12-thread processor built on the Zen 4 architecture, codenamed Phoenix, using a 4 nm process from TSMC. Its base clock is 4.20 GHz with a boost clock of 4.70 GHz, and it carries a 65W TDP. The cache layout includes 64 KB of L1 per core, 1 MB of L2 per core, and 16 MB of shared L3 cache. Memory support is DDR5 over a dual-channel bus, yielding a memory bandwidth of 83.2 GB/s. The processor is unlocked for overclocking and sits on the AMD Socket AM5 platform with 20 PCIe Gen 4 lanes (CPU only).

In synthetic benchmarks, the 8400F shows a clear split between single-thread and multi-thread capability. Its 3DMark single-thread score is 951, while the max-threads score reaches 6165, indicating that scaling from one to many threads yields roughly a 6.5x improvement — a typical figure for a 6-core part. Cinebench R23 results echo this: a single-core score of 2943 versus a multi-core score of 20851. The multi-core result is about 7.1x the single-core number, which is close to the theoretical limit for 6 cores with 12 threads, suggesting efficient thread utilization. PassMark multi-thread performance is 24530, with a single-thread score of 3684.

Relative to other CPUs, the 8400F ranks at the 82nd percentile against all processors. Its closest rivals in average benchmark score are the AMD Ryzen 7 2700X (25057, deltaPct 0), the AMD Ryzen AI 5 PRO 340 (25099, deltaPct -0.1), the AMD EPYC 9474F (25103, deltaPct -0.2), and the AMD Ryzen 5 7500F (24993, deltaPct 0.3). The 8400F's own average benchmark score is 25064. The deltaPct values indicate that the 8400F is essentially tied with the Ryzen 7 2700X (within 0.1% or less) and is slightly ahead of the Ryzen 5 7500F by 0.3%. This positioning matters for Rust, a game that is notoriously CPU-intensive in its simulation of networked worlds, building mechanics, and entity interactions.

For Rust specifically, the 8400F's 6 cores and 12 threads provide a solid base. The game's server-side and client-side logic can leverage multiple threads, but single-thread performance remains critical for frame pacing. The 8400F's strong single-thread score (951 in 3DMark, 2943 in Cinebench R23) suggests it can handle Rust's primary game loop without becoming a bottleneck at lower resolutions. The 16 MB of L3 cache is modest but adequate for a game that often has large working sets due to world streaming. At 1080p with Low settings, the CPU is likely the limiting factor, as the frame rate of 215 fps exceeds what the GPU needs to render at that quality level. The data shows that the CPU's multi-threaded throughput (Cinebench R23 multi-core 20851) aligns with its ability to maintain high frame rates in Rust's less demanding scenes.

GPU Role — VRAM, clocks, and how they relate to this game's results

The NVIDIA GeForce RTX 4080 SUPER is built on the Ada Lovelace architecture with the AD103 chip, fabricated on a 5 nm process by TSMC. It has 16 GB of GDDR6X memory on a 256-bit bus, with a memory bandwidth of 736.3 GB/s. The GPU's base clock is 2295 MHz with a boost clock of 2550 MHz, and the memory runs at an effective 23 Gbps. It houses 10240 shading units, 320 texture mapping units, and 112 raster output units, along with 80 ray tracing cores and 320 tensor cores. The pixel rate is 285.6 GPixel/s and the texture rate is 816.0 GTexel/s, with FP32 performance rated at 52.22 TFLOPS. The TDP is 320W, and it requires a 700W suggested PSU with a 1x 16-pin power connector.

In synthetic GPU benchmarks, the 4080 SUPER posts a 3DMark Steel Nomad DX12 score of 6600, a Geekbench OpenCL score of 246994, and a Geekbench Vulkan score of 226163. PassMark results show a G3D score of 34245 and a GPU compute score of 19822. The GPU ranks at the 88th percentile against all GPUs, with an average benchmark score of 53610. Its nearest rivals include the AMD Radeon RX 6900 XT (53489, deltaPct 0.2), the AMD Radeon Pro W6600M (53414, deltaPct 0.4), the AMD Radeon RX 7700S (52505, deltaPct 2.1), and the NVIDIA GeForce RTX 5070 Ti (52086, deltaPct 2.9). The 4080 SUPER leads the RX 6900 XT by a slim 0.2% margin and is 2.9% ahead of the RTX 5070 Ti.

For Rust, the GPU's role becomes more prominent as resolution and settings increase. At 4K Ultra, the average FPS drops to 50.8, indicating that the GPU is heavily taxed by the game's rendering of large open-world environments, dynamic lighting, and draw distances. The 16 GB of VRAM is ample for Rust's texture streaming at Ultra settings, preventing potential stutter from memory swapping. The high memory bandwidth (736.3 GB/s) supports rapid texture loading as the player moves across the map, which is a common source of frame hitches in survival games. The 4080 SUPER's boost clock of 2550 MHz helps maintain consistent performance in scenes with complex shaders and post-processing effects. The data shows that the GPU is the dominant bottleneck at 4K, particularly at Ultra settings where the frame rate is less than half of what the CPU could theoretically feed.

Resolution Scaling — how FPS drops from 1080p to 4K and what it says about the limiting component

The measured FPS data reveals a clear pattern of resolution scaling. At 1080p Low, the average FPS is 215, which drops to 191.7 at 1440p Low and further to 116.1 at 4K Low. This represents a 46% reduction from 1080p to 4K at Low settings. At High settings, the drop is from 164.8 at 1080p to 114.2 at 1440p, and then to 64.3 at 4K — a 61% reduction from 1080p to 4K. The Ultra settings show the most dramatic scaling: 121 fps at 1080p, 87 fps at 1440p, and 50.8 fps at 4K, a 58% drop from 1080p to 4K.

The scaling behavior identifies the limiting component at each resolution. At 1080p Low, the frame rate of 215 fps is likely CPU-limited, as the GPU has plenty of headroom with minimal rendering work. The 8400F's single-thread performance (951 in 3DMark single-thread) is the probable ceiling here. Moving from 1080p to 1440p at Low settings only drops the frame rate by 23.3 fps (from 215 to 191.7), which is a modest 10.8% reduction. This suggests that the CPU is still the primary bottleneck at 1440p Low, with the GPU beginning to take on more load. At 4K Low, the frame rate falls to 116.1, a 39.4% drop from 1440p — this indicates the GPU is now the limiting factor, as the pixel count quadruples from 1080p to 4K.

For High and Ultra settings, the GPU becomes the dominant bottleneck earlier. At 1080p High, the 164.8 fps is still high, but at 1440p High it drops to 114.2 fps, and at 4K High it falls to 64.3 fps. The Ultra settings show the GPU's strain most clearly: 121 fps at 1080p is respectable, but 4K Ultra at 50.8 fps is only 42% of the 1080p figure. The data indicates that the RTX 4080 SUPER, despite its high compute capability (52.22 TFLOPS), cannot maintain high frame rates at 4K Ultra in Rust due to the game's heavy draw call overhead and geometry complexity. The 16 GB VRAM is not the constraint here; rather, it is the raw rasterization throughput of the GPU at extreme resolutions. The resolution scaling pattern confirms that for this combo, 1080p is CPU-bound, 1440p is a balance point, and 4K is firmly GPU-bound.

Measured FPS Breakdown — resolution by resolution, settings by settings, exact numbers

At 1920x1080, the measured average FPS spans from 215 at Low settings down to 121 at Ultra. The Medium setting yields 184.5 fps, and High yields 164.8 fps. The gap between Low and Medium is 30.5 fps, while the gap between Medium and High is 19.7 fps, and the gap between High and Ultra is 43.8 fps. This shows that the largest performance penalty comes from the Ultra preset, which likely enables more demanding shadow and texture options. The 1080p results are consistently above 120 fps, meaning the combo provides a smooth experience even at Ultra for most players, assuming a 120Hz or lower refresh rate monitor.

At 2560x1440, the frame rates are 191.7 (Low), 134.2 (Medium), 114.2 (High), and 87 (Ultra). The drop from 1080p to 1440p is 23.3 fps at Low, 50.3 fps at Medium, 50.6 fps at High, and 34 fps at Ultra. The percentage reductions are 10.8% for Low, 27.3% for Medium, 30.7% for High, and 28.1% for Ultra. The Medium and High settings take a larger relative hit than Low, which indicates that the GPU is becoming more involved at these quality levels. The 1440p Ultra result of 87 fps is still playable, but it is below the 100 fps threshold that some competitive players target. The 1440p Low result of 191.7 fps shows that the CPU can still drive high frame rates at this resolution, but the GPU is starting to matter more.

At 3840x2160, the frame rates are 116.1 (Low), 77.6 (Medium), 64.3 (High), and 50.8 (Ultra). The drop from 1440p to 4K is 75.6 fps at Low, 56.6 fps at Medium, 49.9 fps at High, and 36.2 fps at Ultra. The percentage reductions are 39.4% for Low, 42.2% for Medium, 43.7% for High, and 41.6% for Ultra. The consistency of the percentage drop (around 40-44%) across all settings at 4K suggests a uniform GPU limitation. The 4K Low result of 116.1 fps is the only 4K setting that exceeds 100 fps, while 4K Ultra at 50.8 fps is the lowest measured value across all resolutions and settings. The data shows that for 4K gaming in Rust, the user must choose between high frame rates (Low settings) and visual fidelity (High or Ultra at 60 fps or below).

How This Combo Ranks — use comboRankInGame vs other tested combos

This particular combination of the AMD Ryzen 5 8400F and the NVIDIA GeForce RTX 4080 SUPER ranks 105th out of 1717 tested combos in Rust. This places it in the top 6.1% of all tested CPU-GPU pairings for this game. The rank of 105 out of 1717 is a strong showing, indicating that this combo delivers above-average performance for Rust specifically. The high rank is likely driven by the RTX 4080 SUPER's ability to handle Rust's GPU-intensive rendering at higher resolutions, combined with the 8400F's capable single-thread performance that prevents CPU bottlenecks at lower resolutions.

The combo's rank relative to its individual components' percentiles is instructive. The CPU ranks at the 82nd percentile among all CPUs, while the GPU ranks at the 88th percentile among all GPUs. The combined system rank of 105 out of 1717 (approximately the 93.9th percentile of combos) is higher than either component's individual percentile. This suggests that the pairing is synergistic for Rust — the GPU's strength at high resolutions complements the CPU's ability to maintain frame rates at lower resolutions, creating a balanced system that performs better than the sum of its parts. The fact that the combo rank exceeds both component percentiles indicates that Rust's workload benefits from this specific pairing, where neither component becomes a severe bottleneck.

The data shows that the combo's rank is not simply the average of the two components' percentiles. A naive average of 82% and 88% would suggest a rank around the 85th percentile, but the actual rank is higher. This discrepancy implies that the RTX 4080 SUPER's 16 GB of VRAM and high memory bandwidth (736.3 GB/s) are particularly beneficial for Rust's large world textures, while the 8400F's 6-core, 12-thread configuration with a 4.70 GHz boost clock provides sufficient CPU throughput to avoid holding the GPU back. The rank of 105 out of 1717 also indicates that there are 104 combos that outperform this one, likely featuring higher-tier CPUs (such as the Ryzen 7 or 9 series) paired with the same or better GPUs, or the same CPU paired with even more powerful GPUs. However, for the vast majority of tested combos (1612 out of 1717), this pairing of the 8400F and RTX 4080 SUPER delivers better or equal performance in Rust.