Microsoft Flight Simulator

Microsoft Flight Simulator is a uniquely demanding title, and the measured frame rates for the Intel Core i5-9400 paired with the AMD Radeon RX 6600 XT reveal a system that is consistently balancing on the edge of playability. The data shows a clear and predictable scaling pattern across resolutions, with the combination delivering its most fluid experience only when graphical load is reduced. This analysis breaks down how the CPU and GPU each contribute to the performance envelope, what settings offer the best experience, and how this specific pairing ranks against the broader field of tested hardware.

Resolution Scaling

The frame rate drop from 1080p to 4K is significant, but the pattern is not uniform across all quality presets. At the High preset, the average frame rate falls from 58.9 FPS at 1920x1080 to 45.8 FPS at 2560x1440, a reduction of roughly 22%. Pushing further to 3840x2160, the average plummets to 33.6 FPS, which is a 43% decline from the 1080p baseline. This steep drop indicates that at 4K, the GPU is being heavily taxed, struggling to maintain fluid motion in a sim known for dense scenery and complex rendering.

The scaling story changes dramatically when the settings are lowered. At the Low preset, the system achieves 101.4 FPS at 1080p, which is an excellent result. At 1440p, that figure drops to 83.1 FPS, and at 4K, it still manages a respectable 57.3 FPS. The delta between 1080p and 4K here is only about 44%, which is a smaller relative drop than what is seen at High settings. This suggests that at Low settings, the bottleneck shifts away from the GPU, allowing the CPU to play a more significant role in maintaining frame rates. The gap between the Low and High presets at 4K is substantial—57.3 FPS versus 33.6 FPS—which underscores how much headroom is available by simply reducing the visual load.

The Ultra preset tells a similar story to High but with a lower floor. The system averages 54.8 FPS at 1080p, which drops to 45.2 FPS at 1440p and finally to 31.6 FPS at 4K. The difference between the High and Ultra presets at 4K is just 2 FPS, indicating that the extra settings in the Ultra preset are not the primary factor limiting performance at that resolution; the GPU is already saturated. In contrast, the jump from Low to Medium at 1080p costs about 25 FPS (from 101.4 to 75.7), showing that the first steps up the quality ladder have the most pronounced impact on frame rate. The data indicates that 4K gaming is only viable at the Low preset, while 1440p offers a balanced middle ground where Medium settings can hold 60 FPS.

CPU Role

The Intel Core i5-9400 is a six-core, six-thread processor based on the Coffee Lake architecture, with a base clock of 2.90 GHz and a boost clock of 4.10 GHz. Its benchmark results show a Cinebench R23 multi-core score of 7969 and a single-core score of 1125, placing it in the 50th percentile of all CPUs. This mid-pack positioning is reflected in the game's performance. The CPU is not a top-tier part, but its six physical cores and 4.10 GHz boost are sufficient to feed the GPU at lower resolutions, where the measured 101.4 FPS at 1080p Low demonstrates that the processor is not the limiting factor in that specific scenario.

However, the CPU's limitations become apparent when considering the game's known sensitivity to single-thread performance. The single-core score of 1125 in Cinebench R23 is modest, and while the boost clock of 4.10 GHz helps, the data suggests that the i5-9400 is adequate but not exceptional for Flight Simulator's simulation-heavy workload. When compared to its nearest rivals, the processor's average benchmark score of 2305 is nearly identical to the Intel Core i3-10305 (2300, deltaPct 0.2) and the Intel Core i3-1125G4 (2299, deltaPct 0.2). It also trails the Intel Core i7-8809G by a negligible margin (2319, deltaPct -0.6). This indicates that in a broad sense, the i5-9400 is essentially on par with other mid-range chips of its era, offering no distinct advantage or disadvantage in raw compute.

In practice, the CPU's role is to maintain a stable frame rate floor. The data shows that at 1080p Low, the system hits 101.4 FPS, which is likely near the CPU's ceiling for this title. As the resolution increases to 1440p and 4K, the frame rate drops, but the fact that the Low preset still delivers 57.3 FPS at 4K suggests the CPU is not causing a catastrophic bottleneck; the GPU is simply overwhelmed by pixel count. The processor's 9 MB of shared L3 cache and dual-channel DDR4 memory support are adequate, but there is no evidence in the data that this CPU provides any special advantage for flight simulators. It is a competent, workmanlike performer that holds its own, but it does not boost the experience beyond what the GPU can deliver.

GPU Role

The AMD Radeon RX 6600 XT is a RDNA 2.0 architecture GPU with 8 GB of GDDR6 memory on a 128-bit bus, offering a memory bandwidth of 256.0 GB/s. Its boost clock is 2589 MHz, and it features 2048 shading units. The GPU's benchmark scores show a Passmark G3D score of 16461, placing it in the 71st percentile of all GPUs. This is a solidly mid-to-upper-tier graphics card, and the data confirms it is the primary driver of visual quality in this pairing.

The GPU's performance in Microsoft Flight Simulator is the main factor behind the resolution scaling observed. At 4K Ultra, the average frame rate is 31.6 FPS, which is below the threshold for smooth play. The card is simply not powerful enough to handle the high pixel count and the game's complex rendering at maximum settings. The 8 GB VRAM is likely a limiting factor at 4K with high-resolution textures, as the card struggles to maintain 33.6 FPS at the High preset. The 256.0 GB/s bandwidth is also modest for 4K workloads, which may contribute to the steep performance drop.

When compared to its nearest rivals, the RX 6600 XT's average benchmark score of 27985 is essentially tied with the NVIDIA GeForce GTX 980 Ti (27956, deltaPct 0.1) and the AMD Radeon R9 M395X (27883, deltaPct 0.4). It sits just below the NVIDIA GeForce RTX 3070 (28238, deltaPct -0.9). This suggests that in raw compute, the RX 6600 XT is a capable performer, but it is not in the same league as higher-end cards. The data shows that the GPU is most comfortable at 1080p, where it can deliver 75.7 FPS at Medium settings and 58.9 FPS at High. At 1440p, it manages 60 FPS at Medium, which is a playable result, but the 45.8 FPS at High shows the card is starting to struggle. The GPU’s 165.7 GPixel/s pixel rate and 331.4 GTexel/s texture rate are sufficient for 1080p and 1440p gaming but are overwhelmed at 4K, where the 33.6 FPS average at High settings is the clearest indicator of its limitations.

Settings Recommendations

Based on the measured data, the optimal balance of visual fidelity and performance for this combo is the Medium preset at 2560x1440, which yields an average of 60 FPS. This is the only resolution and preset combination that hits the 60 FPS mark while maintaining a reasonable level of graphical detail. At 1080p, the Medium preset delivers 75.7 FPS, which is smoother, but the visual upgrade to 1440p is significant, and the 60 FPS average is perfectly playable for a flight simulator.

For users who prioritize frame rate above all else, the Low preset at 1080p offers 101.4 FPS, which is an exceptional result for this title and would provide a very fluid experience. The Low preset at 1440p also remains viable at 83.1 FPS, offering a good middle ground. The High preset is only recommended for 1080p, where it achieves 58.9 FPS, a number that is close to playable but may exhibit occasional dips during complex scenes. The Ultra preset is not recommended for any resolution, as even at 1080p it only manages 54.8 FPS, and the visual improvements over High are marginal in a simulator context. At 4K, only the Low preset is usable, with a 57.3 FPS average, but the visual compromise is steep. The data clearly shows that the Medium preset at 1440p is the sweet spot, offering a stable 60 FPS without sacrificing the core visual experience.

How This Combo Ranks

In the grand scheme of tested hardware combinations, this pairing of the Intel Core i5-9400 and AMD Radeon RX 6600 XT ranks 1327th out of 1795 combos in Microsoft Flight Simulator. This places it in the lower-middle tier of all configurations, which is consistent with the mid-range nature of both components. The rank reflects the reality that while this system is fully capable of running the game, it does not have the headroom to excel at high resolutions or maximum settings.

The rank is a direct consequence of the GPU's limitations at higher resolutions and the CPU's unremarkable standing. The GPU's 71st percentile ranking among all GPUs is solid, but the CPU's 50th percentile ranking drags the overall combo down. The data suggests that this system is best suited for 1080p gaming with high settings, or 1440p gaming with medium settings, as these scenarios keep the frame rate at playable levels. For a flight sim that rewards high frame rates for smooth camera control, the 1327th rank out of 1795 combos indicates that users should temper their expectations. The system is not a top performer, but it is also not a failure; it sits comfortably in the middle of the pack, offering a balanced, if not spectacular, experience. The measured data shows that with careful settings management, this combo can provide a satisfying simulation experience, but it will never be a benchmark leader.