Fortnite

The AMD Ryzen 5 8400F paired with the Intel Arc B390 presents a unique case study in system bottlenecking. The benchmark data for Fortnite shows a configuration where the CPU’s substantial processing power is almost entirely neutralized by the GPU’s output limits, creating a lopsided performance profile that becomes more apparent as resolution and settings change.

Resolution Scaling

The measured FPS data shows a steep and consistent decline as resolution increases from 1920x1080 to 3840x2160. At Low settings, the average frame rate drops from 115 FPS at 1080p to 73 FPS at 1440p, a reduction of 42 FPS. Moving from 1440p to 4K at Low settings, the average falls further to 39 FPS. This pattern indicates that the GPU is the dominant limiting factor, as the workload per pixel increases with resolution and the Arc B390’s compute resources (1536 shading units) become saturated.

The scaling from Medium to High settings at each resolution reinforces this. At 1080p, High settings produce 63 FPS average, while Medium produces 81 FPS. At 1440p, these figures drop to 40 FPS and 51 FPS respectively. At 4K, High delivers only 21 FPS, and Medium drops to 27 FPS. The relative performance gap between resolutions widens at higher settings, which is typical for a GPU-bound scenario where the fill rate and shading capacity are stretched thin. The Ultra preset, which pushes the hardware hardest, yields just 41 FPS at 1080p, 26 FPS at 1440p, and 14 FPS at 4K.

The data suggests that the 4K resolution is largely impractical for this combo, with even Low settings failing to reach 40 FPS average. The jump from 1080p to 1440p at Low settings cuts performance by roughly 37%, indicating the GPU’s memory bandwidth limitation, listed as "System Dependent," plays a critical role. The drop from 1440p to 4K is even more severe, with performance nearly halving again. This scaling behavior points to the Intel Arc B390 being the primary constraint, with the CPU having ample headroom to spare.

GPU Role

The Intel Arc B390’s specifications reveal why it struggles under load. Its memory configuration is "System Shared," meaning it relies on the system’s DDR5 memory rather than dedicated VRAM. This creates a bottleneck for a fast-paced game like Fortnite, which requires rapid texture streaming and frame buffer access. The base clock is a low 300 MHz, boosting to 2500 MHz, but the shared memory architecture limits effective throughput.

The GPU’s benchmark scores are telling. In 3dmark_steel_nomad_dx12, it scores 1482, placing it in the 9th percentile of all GPUs. Its nearest rivals include the NVIDIA GeForce GT 520MX (1463, 1.3% higher), NVIDIA GeForce 800M (1460, 1.5% higher), and NVIDIA GeForce GT 625 OEM (1446, 2.5% higher). These are all legacy entry-level mobile or OEM parts, which contextualizes the Arc B390’s performance class. The FP32 compute is rated at 7.680 TFLOPS, but this raw number does not translate to playable frame rates in Fortnite at higher settings due to the shared memory bottleneck.

The GPU’s pixel rate of 60.00 GPixel/s and texture rate of 120.0 GTexel/s are modest figures. At 4K resolution, the GPU is asked to fill over 8 million pixels per frame, and with only 24 ROPs, it cannot keep up with the demands of even Medium settings. The 12 RT cores are irrelevant for Fortnite’s standard rendering path, and the 3 nm process node does not compensate for the fundamental architectural limitation of shared memory. The data shows that the GPU is the clear performance ceiling, as evidenced by the dramatic FPS drops when resolution or settings are increased.

How This Combo Ranks

In the context of other tested combinations, this CPU-GPU pairing ranks 2417 out of 2740 combos in Fortnite. This places it in the bottom 12% of tested systems, a poor showing that reflects the GPU’s entry-level status. The CPU itself is a strong performer, with an average benchmark score of 25005 and a percentile rank of 77 among all CPUs. Its nearest rivals are the AMD Ryzen 5 7500F (24964, 0.2% higher), Intel Core i7-11850H (24935, 0.3% higher), and Intel Core i7-13620H (24911, 0.4% higher), showing the 8400F is competitive with these mid-range parts.

The discrepancy between the CPU’s high percentile (77) and the combo’s low rank (2417) highlights a severe imbalance. The CPU is performing at a level that would support much higher frame rates, but the GPU holds the system back. This rank is not a reflection of the CPU’s capability, but rather a measure of the combined system’s gaming output. The data suggests that this combo is poorly matched for Fortnite, with the GPU acting as a severe drag on the overall experience. For context, the CPU’s single-thread score in 3dmark is 951, and its multi-thread score is 6165, both of which are solid, yet the system cannot translate this into smooth gameplay due to the GPU.

Measured FPS Breakdown

At 1920x1080, the benchmark results show a clear hierarchy across settings. Low settings achieve an average of 115 FPS, which is the only playable range for competitive gaming. Medium settings drop to 81 FPS average, with a minimum of 69 FPS and maximum of 93 FPS, indicating some frame time variance. High settings fall to 63 FPS average, while Ultra drops significantly to 41 FPS average. These numbers suggest that 1080p is the only resolution where the combo can approach a smooth experience, but only at lower presets.

Moving to 2560x1440, the performance degrades noticeably. Low settings average 73 FPS, which is a 42 FPS drop from 1080p. Medium settings average 51 FPS, with a minimum of 44 FPS and maximum of 59 FPS. High settings produce 40 FPS average, and Ultra drops to 26 FPS average. At this resolution, even Low settings begin to feel marginal for fast-paced gameplay, and Medium settings show frame dips that could cause stuttering in action-heavy scenes.

At 3840x2160, the combo is largely unplayable. Low settings average 39 FPS, which is below the threshold for smooth motion. Medium settings average 27 FPS, with a minimum of 23 FPS and maximum of 31 FPS, showing significant frame pacing issues. High settings average 21 FPS, and Ultra drops to 14 FPS average. The data indicates that 4K is not viable for this game with this hardware, as even the lowest settings fail to maintain a consistent frame rate.

FAQ

Q: What is the best resolution for this combo in Fortnite?

A: The data shows 1920x1080 is the only resolution where the combo achieves consistently high frame rates. At Low settings, it averages 115 FPS, while Medium settings average 81 FPS. Higher resolutions see a dramatic drop, with 1440p Low averaging 73 FPS and 4K Low averaging 39 FPS.

Q: How does the CPU’s performance compare to its rivals?

A: The AMD Ryzen 5 8400F has an average benchmark score of 25005, placing it 0.2% lower than the AMD Ryzen 5 7500F (24964), 0.3% lower than the Intel Core i7-11850H (24935), and 0.4% lower than the Intel Core i7-13620H (24911). It also scores 0.4% higher than the AMD EPYC 9474F (25103).

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

A: The difference is 74 FPS. Low settings average 115 FPS, while Ultra settings average 41 FPS. Medium settings sit between at 81 FPS, showing a steep performance cost for higher visual fidelity.

Q: Is there any resolution where the Ultra preset is playable?

A: No. The Ultra preset averages 41 FPS at 1080p, 26 FPS at 1440p, and 14 FPS at 4K. None of these meet the 60 FPS threshold for smooth gameplay, indicating this preset is not viable with this hardware.

Q: How does the GPU’s benchmark score rank against other GPUs?

A: The Intel Arc B390 scores 1482 in 3dmark_steel_nomad_dx12, placing it in the 9th percentile of all GPUs. Its closest rival is the NVIDIA GeForce GT 520MX, which scores 1463 (1.3% lower), followed by the NVIDIA GeForce 800M at 1460 (1.5% lower).

Q: What are the minimum FPS values recorded for Medium settings?

A: At 1080p Medium, the minimum FPS is 69. At 1440p Medium, it drops to 44 FPS. At 4K Medium, the minimum is 23 FPS. These values show increasing frame instability at higher resolutions.

Settings Recommendations

Based on the measured data, the only viable configuration for a smooth experience is 1920x1080 with Low settings. This preset achieves an average of 115 FPS, which is suitable for the fast-paced nature of Fortnite. Medium settings at 1080p produce 81 FPS average, which is still playable, but the minimum of 69 FPS suggests occasional dips that could be noticeable during intense combat. For players prioritizing frame rate, Low settings at 1080p is the clear choice.

At 1440p, the data shows that Low settings average 73 FPS, which is borderline acceptable for casual play but may feel inconsistent. Medium settings at 1440p average 51 FPS with a minimum of 44 FPS, which is too low for competitive play. The High and Ultra presets at this resolution are not recommended, as they drop below 40 FPS average. For 4K, the data strongly advises against any preset, as even Low settings fail to reach 40 FPS average.

The Ultra preset is universally poor across all resolutions, with the highest average of 41 FPS at 1080p. This suggests the GPU lacks the raw throughput for the enhanced effects and draw distances that Ultra enables. The data supports a strategy of sacrificing visual quality for performance, particularly at 1080p, where the combo can still deliver a high frame rate. The Medium preset at 1080p offers a balanced compromise, but the Low preset is the only one that approaches the high refresh rates that competitive Fortnite players seek.

CPU Role

The AMD Ryzen 5 8400F is a 6-core, 12-thread processor based on the Zen 4 architecture, codenamed Phoenix. It has a base clock of 4.20 GHz and a boost clock of 4.70 GHz, with a 65 W TDP. The CPU’s benchmark results are strong, with a Cinebench R23 multi-core score of 20851 and a single-core score of 2943. Its 3dmark scores scale linearly from 1874 at 2 threads to 6165 at max threads, indicating good multi-threading efficiency.

Given these specifications, the CPU is more than capable of handling Fortnite’s game logic and physics, which typically rely on a few cores. The 12 threads provide ample headroom for background processes and streaming. The CPU’s percentile rank of 77 among all CPUs confirms it is a capable processor for gaming. However, the measured FPS data shows that its potential is unrealized in this pairing.

The bottleneck is clearly the GPU, as the CPU’s performance does not degrade with the resolution increases. At 1080p Low, the system achieves 115 FPS, but this is limited by the GPU’s rendering capacity, not the CPU’s processing speed. The CPU’s L3 cache of 16 MB (shared) and dual-channel DDR5 memory support with 83.2 GB/s bandwidth are sufficient for Fortnite’s demands. The data implies that if paired with a stronger GPU, this CPU could easily push frame rates beyond the 115 FPS seen here, but with the Arc B390, it is left waiting for the GPU to catch up.