Rust

The Intel Core i5-9400 paired with the Intel Arc B390 produces a combination that ranks near the bottom of the database for Rust, landing at position 2601 out of 2953 tested combos. This places the system in the 12th percentile of all tested configurations, indicating that while the hardware is functional for basic gameplay, it struggles to deliver competitive performance in this demanding survival title. The benchmark data reveals a system that is heavily constrained by its graphics solution, with the CPU showing moderate capability while the GPU consistently bottlenecks performance across all tested resolutions and settings.

FAQ

Q: How does this combo rank among all tested systems in Rust?

A: The combination ranks 2601 out of 2953 tested combos, placing it in the bottom 12% of all configurations. This indicates a system that will struggle with high settings but remains usable for lower-end gameplay.

Q: What is the best average FPS achievable with this hardware?

A: The highest average FPS recorded is 76 at 1080p with Low settings. This is the only configuration that breaks the 60 FPS threshold, making it the sole viable option for smooth gameplay.

Q: How does the GPU compare to its nearest rivals in synthetic benchmarks?

A: The Arc B390 scores 1482 in 3DMark Steel Nomad DX12, which is 1.3% ahead of the NVIDIA GeForce GT 520MX (1463), 1.5% ahead of the GeForce 800M (1460), 2.5% ahead of the GT 625 OEM (1446), and 2.7% ahead of the GT 710 (1443). These are extremely tight margins, showing the B390 sits at the very bottom of the GPU performance spectrum.

Q: What is the CPU's percentile ranking among all processors?

A: The Core i5-9400 sits at the 47th percentile of all CPUs, placing it squarely in the mid-range category. Its average benchmark score of 2254 is nearly identical to its closest rivals, with deltas of only -0.2% to 0.4% against the i7-1068NG7, i7-10710U, Ryzen 5 PRO 1500, and i3-10305.

Q: Does the GPU have dedicated VRAM?

A: No, the Arc B390 uses System Shared memory, meaning its memory size, type, bus width, and bandwidth are all dependent on the system's main RAM configuration. This is a significant limitation for a game like Rust that benefits from dedicated graphics memory.

Q: What is the difference between Low and Ultra settings at 1080p?

A: At 1080p, Low settings produce 76 FPS average, while Ultra drops to 33 FPS average. This represents a 56.6% performance decrease when moving from the lowest to the highest quality preset, demonstrating the GPU's limited headroom for visual enhancements.

GPU Role

The Intel Arc B390 is an integrated graphics solution based on the Xe3-LPG architecture, built on a 3 nm process from Intel. It operates with a base clock of 300 MHz and a boost clock of 2500 MHz, featuring 1536 shading units, 48 texture mapping units, and 24 raster output units. The GPU includes 12 ray tracing cores but lacks dedicated tensor cores, and its memory subsystem is entirely System Shared, making performance heavily dependent on the host system's RAM configuration.

In synthetic benchmarks, the Arc B390 scores 1482 in 3DMark Steel Nomad DX12, which places it at the 9th percentile of all GPUs. Its nearest rivals are all legacy NVIDIA parts: the GT 520MX, GeForce 800M, GT 625 OEM, and GT 710, with performance deltas ranging from 1.3% to 2.7%. This positions the B390 as a GPU that is technically modern but performs at the level of decade-old entry-level discrete graphics, which explains its struggles in Rust.

The GPU's measured performance in Rust directly reflects its low benchmark standing. At 1080p with Low settings, it manages 76 FPS, but this drops to 51 FPS at Medium, 43 FPS at High, and 33 FPS at Ultra. The pattern shows that the B390 has enough raw compute for low-fidelity rendering but quickly runs out of headroom as texture quality, lighting, and draw distances increase. The System Shared memory further compounds the issue, as Rust's large world and frequent asset loading place heavy demands on memory bandwidth that integrated solutions cannot adequately supply.

The pixel rate of 60.00 GPixel/s and texture rate of 120.0 GTexel/s suggest the GPU has theoretical capability, but the 7.680 TFLOPS FP32 performance is modest by modern standards. The 12 ray tracing cores are present but provide little practical benefit in Rust, which does not heavily utilize ray tracing. The GPU's 80 W TDP and IGP slot width confirm its integrated nature, and the lack of dedicated power connectors means it draws from the same thermal and power budget as the CPU, potentially causing thermal throttling in sustained gameplay sessions.

Measured FPS Breakdown

At 3840x2160 (4K), the Arc B390 produces its lowest results across all settings. Low settings yield an average of 31 FPS, while Medium drops to 21 FPS with a range of 18 to 24 FPS. High settings reduce the average to 18 FPS, and Ultra falls to 13 FPS. These numbers indicate that 4K resolution is essentially unplayable for this combo, with even the lowest settings failing to reach 30 FPS consistently.

Moving to 2560x1440 (1440p), the performance improves but remains constrained. Low settings achieve 53 FPS average, which is the only playable configuration at this resolution. Medium settings produce 35 FPS with a range of 30 to 41 FPS, High drops to 30 FPS, and Ultra falls to 23 FPS. The step from Low to Medium represents a 34% performance loss, showing that the GPU cannot handle moderate quality increases at this resolution.

At 1920x1080 (1080p), the combo shows its best results. Low settings reach 76 FPS average, providing a smooth experience for competitive play. Medium settings produce 51 FPS with a range of 44 to 59 FPS, which is borderline playable for most users. High settings drop to 43 FPS, and Ultra falls to 33 FPS. The data shows that only Low settings at 1080p consistently deliver frame rates above 60 FPS, while Medium settings hover near the edge of playability.

The measured FPS values follow a consistent pattern across all resolutions: Low settings provide roughly double the performance of Ultra settings. This ratio holds true at 1080p (76 vs 33), 1440p (53 vs 23), and 4K (31 vs 13). The consistent scaling suggests that the GPU's architectural limitations, rather than memory bandwidth or CPU bottlenecks, are the primary constraint on performance.

Resolution Scaling

The performance drop from 1080p to 4K is severe and consistent across all settings. At Low settings, the average FPS falls from 76 at 1080p to 53 at 1440p (a 30.3% decrease) and then to 31 at 4K (a 41.5% decrease from 1440p). Overall, moving from 1080p to 4K at Low settings results in a 59.2% performance loss. Medium settings show a similar trend: 51 FPS at 1080p drops to 35 FPS at 1440p (31.4% decrease) and 21 FPS at 4K (40% decrease), for a total loss of 58.8% from 1080p to 4K.

The scaling pattern reveals that the GPU is the limiting component at every resolution. If the CPU were the bottleneck, we would expect to see smaller performance differences between resolutions, as lower resolutions reduce GPU load while keeping CPU load constant. Instead, the data shows that each resolution increase produces a nearly proportional drop in frame rate, indicating that the Arc B390's rendering capabilities are fully saturated even at 1080p.

High settings follow the same pattern: 43 FPS at 1080p, 30 FPS at 1440p (30.2% decrease), and 18 FPS at 4K (40% decrease), totaling a 58.1% loss from 1080p to 4K. Ultra settings drop from 33 FPS at 1080p to 23 FPS at 1440p (30.3% decrease) to 13 FPS at 4K (43.5% decrease), for a total of 60.6% reduction. The consistency of these percentages across all settings confirms that resolution scaling is purely GPU-bound.

The 30% reduction from 1080p to 1440p and the additional 40% reduction from 1440p to 4K are characteristic of a GPU that has insufficient fill rate and memory bandwidth for higher resolutions. The System Shared memory architecture means that as resolution increases, the GPU must access more data from system RAM, which is slower than dedicated VRAM. This explains why the performance drops are so pronounced at 4K, where the memory bandwidth demands become prohibitive.

Settings Recommendations

Based on the measured FPS data, the only configuration that provides a consistently smooth experience is 1080p with Low settings, which achieves 76 FPS average. This should be the default recommendation for any user seeking playable performance with this hardware. The 76 FPS result indicates that the GPU has enough headroom for occasional dips without falling below playable thresholds, though no minimum FPS data is available for this configuration.

For users who prioritize visual quality over frame rate, 1080p Medium is the next viable option at 51 FPS average, with recorded minimums of 44 FPS and maximums of 59 FPS. This configuration offers a balance between fidelity and playability, though users should expect occasional frame drops during intense moments. The 44 FPS minimum suggests that the experience will remain playable but may feel less smooth than the Low settings option.

At 1440p, only Low settings (53 FPS average) approach playability, but even this configuration lacks the headroom of the 1080p Low option. Medium settings at 1440p produce 35 FPS average with a minimum of 30 FPS, which is below the 60 FPS threshold most players consider ideal for competitive survival gameplay. High and Ultra settings at 1440p, along with all 4K configurations, produce frame rates below 30 FPS and should be avoided entirely.

The data clearly indicates that this combo is best suited for 1080p gaming with reduced visual settings. Users should start with 1080p Low and adjust upward to Medium only if they can tolerate average frame rates in the 50s. The 33 FPS average at 1080p Ultra demonstrates that even at the lowest resolution, the highest quality preset overwhelms the GPU's capabilities. For Rust specifically, where fast reactions and smooth camera movement are important, prioritizing frame rate over visual fidelity is the correct approach.

CPU Role

The Intel Core i5-9400 is a 6-core, 6-thread processor from the Coffee Lake Refresh generation, built on a 14 nm process. It operates with a base clock of 2.90 GHz and a boost clock of 4.10 GHz, with a 65 W TDP. The CPU features 64 KB of L1 cache per core, 256 KB of L2 cache per core, and 9 MB of shared L3 cache. Memory support is limited to DDR4 with dual-channel configuration and 42.7 GB/s bandwidth.

In synthetic benchmarks, the i5-9400 scores 6629 in Cinebench R23 multi-core and 935 in single-core. Its average benchmark score of 2254 places it at the 47th percentile of all CPUs, which is a solid mid-range position. The nearest rivals show remarkably tight competition: the i7-1068NG7 scores 2259 (-0.2% delta), the i3-10305 scores 2264 (-0.4% delta), the i7-10710U scores 2248 (+0.3% delta), and the Ryzen 5 PRO 1500 scores 2246 (+0.4% delta). This indicates that the i5-9400's CPU performance is essentially interchangeable with these other mid-range parts.

In the context of Rust gameplay, the CPU's role is significant but secondary to the GPU's limitations. The 6-core, 6-thread configuration is sufficient for Rust's threading model, which can utilize multiple cores for world simulation and entity processing. However, the measured FPS data shows that the GPU bottleneck dominates at all settings and resolutions. If the CPU were the limiting factor, we would expect to see frame rates that remain constant across different graphics settings, but the data shows dramatic FPS changes when moving from Low to Ultra, confirming GPU limitation.

The CPU's 47th percentile ranking suggests it is capable of feeding the Arc B390 adequately at lower settings, but the GPU's 9th percentile ranking means it cannot translate CPU capability into high frame rates. The 76 FPS at 1080p Low is likely near the ceiling of what this CPU-GPU pairing can achieve, with the CPU providing enough single-thread performance (935 in Cinebench R23 single-core) to handle Rust's game logic while the GPU renders frames. The 4.10 GHz boost clock helps maintain responsive gameplay, but the 6-thread limit may cause occasional hitches in heavily populated areas of the game world.

The CPU's DDR4 memory support with 42.7 GB/s bandwidth is adequate for the i5-9400's needs, but the Arc B390's System Shared memory architecture means the CPU and GPU compete for the same memory bandwidth. This shared resource contention likely contributes to the performance drop at higher resolutions, where the GPU requires more memory bandwidth for larger framebuffers and textures. The 9 MB L3 cache helps mitigate some of this contention, but it is insufficient to overcome the fundamental limitation of shared memory in a game as demanding as Rust.