Fortnite

The Intel Core i5-9400 paired with the NVIDIA GeForce RTX 4080 lands at rank 587 out of 3,700 tested combos for Fortnite, placing it in the top 16% of all configurations. This is a significant achievement given that the CPU is a six-core, six-thread Coffee Lake part from 2018 that sits at only the 47th percentile among all CPUs in general benchmark scores. The data indicates that this combination is heavily GPU-favored, as the RTX 4080 operates at the 86th percentile among all GPUs, and the pairing produces frame rates that are competitive with much more modern processor combinations.

How This Combo Ranks

The combo rank of 587 out of 3,700 tested configurations places this system in the 84th percentile of all CPU-GPU pairings for Fortnite. That means roughly 84% of all tested combos perform at or below this level, while the remaining 16% deliver higher average frame rates. The ranking is particularly noteworthy when considering the age of the processor—the i5-9400 was released in October 2018 and is classified as end-of-life, yet it still achieves a top-sixth percentile result when paired with a flagship-tier GPU.

Looking at the CPU's general benchmark standing, its average benchmark score of 2,254 places it just 0.2% below the Intel Core i7-1068NG7 and only 0.4% above the AMD Ryzen 5 PRO 1500. In contrast, the RTX 4080's average score of 54,247 is essentially a statistical tie with the RTX 4080 SUPER (0.1% higher) and sits 2.7% above the AMD Radeon 8060S. This disparity in relative standing between the two components explains why the combo ranks where it does: the GPU is doing the heavy lifting, while the CPU is operating near the bottom of its peer group for modern gaming workloads.

The measured frame rates reinforce this interpretation. At 1080p Low settings, the system produces 290 FPS, which is only 40 FPS higher than the 1080p High preset at 232 FPS. This relatively small gap between Low and High at 1080p suggests that the CPU is beginning to cap performance, as a purely GPU-limited scenario would show a much larger difference between those two presets.

GPU Role

The NVIDIA GeForce RTX 4080 brings 16 GB of GDDR6X memory on a 256-bit bus, yielding a memory bandwidth of 716.8 GB/s. The GPU operates at a base clock of 2205 MHz with a boost clock of 2505 MHz, and memory runs at 1400 MHz with 22.4 Gbps effective speed. These specifications place it firmly in the high-end segment, with 9,728 shading units, 304 TMUs, and 112 ROPs available for rasterization work.

In Fortnite, the GPU's role becomes more dominant as resolution increases. The data shows that at 4K Ultra, the average frame rate drops to 52 FPS, while 4K High produces 79 FPS. The GPU is clearly the limiting factor at this resolution, as the 4K Ultra preset demands more from the 4080 than the 16 GB of VRAM and 48.74 TFLOPS of FP32 compute can sustain at high frame rates. The 4K Medium preset with a minimum FPS of 87 and maximum of 118 shows that the GPU can maintain playable rates when settings are moderated.

The GPU's percentile standing of 86% among all GPUs, combined with its average benchmark score of 54,247, indicates that it is a top-tier part. However, the gap between its nearest rivals is telling: the RTX 4080 SUPER scores 54,209 (0.1% lower), and the AMD Radeon Pro W5700X scores 54,828 (1.1% higher). These differences are within noise, meaning the 4080 is performing exactly as expected for its class.

Settings Recommendations

The optimal settings for this combo depend on the target resolution and desired frame rate. At 1080p, the High preset delivers 232 FPS average, which is already well above the refresh rate of most gaming monitors. The Medium preset at 255 FPS offers a 23 FPS improvement over High, and Low pushes further to 290 FPS. However, the gains from dropping from High to Low are modest relative to the visual fidelity loss, suggesting that 1080p High is the best balance.

At 1440p, the High preset produces 150 FPS average, which is still excellent for competitive play. The Medium preset at 194 FPS is 44 FPS higher than High, making it the best choice for players with 144Hz or 165Hz displays who want to push maximum frame rates. The Low preset at 250 FPS is available but offers diminishing returns over Medium given the visual quality sacrifice.

For 4K gaming, the Medium preset at 102 FPS average (with a minimum of 87 FPS) is the recommended starting point, as it maintains a playable experience above 60 FPS throughout. The High preset at 79 FPS is also viable for players who prefer visual quality over frame rate, but the Ultra preset at 52 FPS average drops below the 60 FPS threshold and should be avoided for competitive play.

Measured FPS Breakdown

At 1920x1080, the data shows a clear progression across presets. Low settings yield 290 FPS average, Medium produces 255 FPS with a minimum of 216 and maximum of 293, High delivers 232 FPS, and Ultra drops to 156 FPS. The gap between Low and Ultra is 134 FPS, representing a 46% reduction in frame rate when moving from the lowest to the highest quality preset.

At 2560x1440, the same pattern emerges but with lower absolute numbers. Low settings produce 250 FPS, Medium delivers 194 FPS with a minimum of 165 and maximum of 223, High yields 150 FPS, and Ultra falls to 99 FPS. The delta between Low and Ultra at 1440p is 151 FPS, which is a 60% reduction.

At 3840x2160, the frame rate ceiling drops significantly. Low settings still manage 145 FPS, Medium produces 102 FPS with a minimum of 87 and maximum of 118, High delivers 79 FPS, and Ultra drops to 52 FPS. The span between Low and Ultra at 4K is 93 FPS, a 64% reduction, indicating that the GPU is becoming the dominant bottleneck at this resolution.

Resolution Scaling

Moving from 1080p to 1440p at High settings, the frame rate drops from 232 FPS to 150 FPS, a 35% reduction. From 1440p to 4K at High, the frame rate falls from 150 FPS to 79 FPS, a 47% reduction. This accelerating decline as resolution increases points to the GPU being the primary limiting component at higher resolutions, while the CPU can keep up with the frame rate demands at 1080p.

The Low preset tells a similar story but with different magnitudes. From 1080p Low (290 FPS) to 1440p Low (250 FPS), the drop is only 14%. However, from 1440p Low to 4K Low (145 FPS), the reduction jumps to 42%. This non-linear scaling suggests that the RTX 4080 has enough headroom at lower resolutions to be partially constrained by the CPU, but at 4K the GPU's compute and memory bandwidth become the binding constraint.

The Medium preset, which has minimum and maximum data points, shows the tightest frame time distribution. At 1080p Medium, the range is 216-293 FPS (77 FPS spread). At 1440p Medium, the range narrows to 165-223 FPS (58 FPS spread). At 4K Medium, the range tightens further to 87-118 FPS (31 FPS spread). This pattern indicates that as resolution increases, frame pacing becomes more consistent, which is characteristic of a GPU-bound scenario where the rendering workload dominates.

CPU Role

The Intel Core i5-9400 features 6 cores and 6 threads with a base clock of 2.90 GHz and a boost clock of 4.10 GHz. It has a 65W TDP and is built on Intel's 14 nm Coffee Lake architecture. The L3 cache is 9 MB shared, with 64 KB L1 and 256 KB L2 per core. Memory support is DDR4 with dual-channel configuration and 42.7 GB/s bandwidth. The CPU supports PCIe Gen 3 with 16 lanes and includes UHD 630 integrated graphics, though these are irrelevant for gaming with a discrete GPU.

The CPU's benchmark results show a single-core Cinebench R23 score of 935 and a multi-core score of 6,629. In Geekbench, it scores 1,389 single-core and 5,141 multi-core. These numbers place it at the 47th percentile among all CPUs, with an average benchmark score of 2,254. The nearest rivals are tightly clustered: the Intel Core i7-1068NG7 at 2,259 (0.2% higher), the Intel Core i3-10305 at 2,264 (0.4% higher), and the AMD Ryzen 5 PRO 1500 at 2,246 (0.4% lower).

In Fortnite, the CPU's role is most evident at lower resolutions. The fact that 1080p Low (290 FPS) is only 35 FPS higher than 1080p High (232 FPS) suggests that the processor is approaching its limit for feeding the GPU with draw calls and game logic. The 6-core, 6-thread configuration lacks hyper-threading, which can cause frame rate hits in scenes with many players or building structures, though the measured data does not break down these scenarios individually.

The 4.10 GHz boost clock helps mitigate the lack of threads in a game like Fortnite, which relies heavily on single-core performance. The CPU's single-core Cinebench R23 score of 935 is adequate for maintaining 290 FPS at 1080p Low, but the data shows that pushing beyond that threshold is not achievable with this processor, regardless of GPU headroom.

FAQ

Q: Can this combo run Fortnite at 4K with high frame rates?

A: At 4K High settings, the average frame rate is 79 FPS, while 4K Medium produces 102 FPS average with a minimum of 87 FPS. For 4K gaming above 100 FPS, the Medium preset is the highest achievable setting.

Q: What is the highest FPS this system can produce?

A: The maximum measured average is 290 FPS at 1920x1080 with Low settings. The 1080p Medium preset reaches 255 FPS average with a maximum of 293 FPS, and 1080p High yields 232 FPS.

Q: Is the CPU or GPU the bottleneck at 1440p?

A: At 1440p High, the system produces 150 FPS, and 1440p Low reaches 250 FPS. The 100 FPS difference between these settings indicates the GPU is still the primary limiter at this resolution, though the CPU's 6 threads may constrain peak frame rates.

Q: How does this combo compare to other tested configurations?

A: The combo ranks 587 out of 3,700 tested pairs, placing it in the top 16%. The RTX 4080 performs within 0.1% of the RTX 4080 SUPER and 2.7% above the AMD Radeon 8060S in average benchmark scores.

Q: What settings should I use for competitive play at 1080p?

A: The High preset at 232 FPS is recommended, as it provides a 23 FPS improvement over Medium at 255 FPS is marginal, but dropping to Low at 290 FPS sacrifices visual quality for a 58 FPS gain over High.

Q: Does the system maintain consistent frame times at 4K?

A: At 4K Medium, the measured range is 87-118 FPS, a 31 FPS spread. This is the tightest frame time distribution across all tested resolutions, indicating stable performance at 4K with Medium settings.