Thief

The Intel Core i5-9400 is a six-core, six-thread desktop processor from the Coffee Lake architecture, running at a base clock of 2.90 GHz and a boost clock of 4.10 GHz. It utilizes 9 MB of shared L3 cache and supports dual-channel DDR4 memory. In synthetic testing, the chip posts a Cinebench R23 multi-core score of 7969 and a single-core score of 1125, placing it at the 50th percentile among all CPUs. Its average benchmark score of 2305 is nearly identical to the Intel Core i3-10305, which scores 2300, and the Intel Core i3-1125G4, which scores 2299, showing a delta of just 0.2% in both cases. The data suggests this processor is a solid mid-range part for gaming, but it is not a top-tier performer; it trails the Intel Core i7-8809G by 0.6% in average score (2319 vs. 2305). For a 2014 title like Thief, the 9400’s six physical cores are more than sufficient to feed a modern GPU, as the game’s engine is not heavily threaded by modern standards. The benchmark results in this page show that the CPU does not become a bottleneck at any resolution tested, as frame rates scale predictably with GPU load rather than hitting a hard CPU wall. Given its 65W TDP and lack of an unlocked multiplier, this is a straightforward, dependable processor that holds its own in this older title, though its single-core Cinebench R15 score of 113 indicates it is not a speed demon for lightly-threaded tasks.

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

The Core i5-9400’s six cores and six threads are the key factor here. Thief, released in 2014, was designed for quad-core CPUs of that era, so the 9400 provides ample headroom for the game’s AI, physics, and streaming systems. The base clock of 2.90 GHz and boost clock of 4.10 GHz mean that even when only a few cores are active, the processor can ramp up to handle the game’s single-threaded bottlenecks, which are common in stealth titles where AI calculations for enemy sight and sound are processed sequentially. The benchmark data confirms this: at 1080p Low settings, the system achieves 117.4 FPS, which is the highest frame rate recorded in this test suite. That figure is only 9.3% higher than the 1080p High result of 95.6 FPS, indicating that the CPU is not the limiting factor even at lower settings where GPU load is reduced. The processor’s 9 MB of shared L3 cache is also beneficial, as it reduces the latency for frequently accessed game data, though the impact is minor in a title this old. Compared to its nearest rivals, the i5-9400’s average benchmark score of 2305 is virtually tied with the i3-10305 (2300) and i3-1125G4 (2299), so you can expect similar frame pacing in CPU-bound scenarios. The 50th percentile ranking against all CPUs underscores that this is an average modern processor, but for Thief, average is more than enough. The game’s measured FPS at 1080p Ultra (94.6 FPS) versus 1080p Low (117.4 FPS) shows a 24% difference, which is entirely attributable to GPU workload, not CPU limitations. In short, the 9400 will not hold back the RX 6800 XT in this game, and the data supports that conclusion.

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

The AMD Radeon RX 6800 XT is a RDNA 2.0 architecture GPU with 16 GB of GDDR6 memory on a 256-bit bus, delivering 512.0 GB/s of bandwidth. Its base clock is 1825 MHz, with a game clock of 2015 MHz and a boost clock of 2250 MHz. This is a high-end card, sitting at the 87th percentile of all GPUs, with an average benchmark score of 49982. That places it just 0.5% ahead of the Intel Arc A550M (49737) and 2.6% ahead of the NVIDIA GeForce RTX 4070 Ti SUPER (48704), while trailing the NVIDIA RTX A1000 by 1.7% (50826). For Thief, the GPU’s 16 GB of VRAM is overkill, as the game from 2014 will not come close to using even half of that capacity at 4K Ultra. The high boost clock of 2250 MHz ensures that the card’s 4608 shading units are fed with data quickly, which is crucial for maintaining high frame rates in a game that relies on complex lighting and shadow calculations. The measured FPS data shows the GPU is the dominant component in this pairing, as frame rates drop significantly when resolution increases. For example, going from 1080p High (95.6 FPS) to 1440p High (88.2 FPS) is a 7.7% drop, but going from 1440p High to 4K High (57.5 FPS) is a 34.8% drop. This steep decline at 4K is a classic sign of GPU-bound rendering, where the card’s raw compute power and memory bandwidth are stretched to their limits. The GPU’s 512.0 GB/s bandwidth is sufficient for 4K textures, but the sheer pixel count of 3840x2160 overwhelms the card’s pixel rate of 288.0 GPixel/s, resulting in the lower frame rates seen in the data.

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 GPU-bound scaling. Starting at 1080p Ultra, the system achieves 94.6 FPS. Moving to 1440p Ultra, the frame rate drops to 83.3 FPS, a 12% reduction. Jumping to 4K Ultra, the frame rate falls to 54.5 FPS, which is a 35% drop from the 1440p figure and a 42% drop from 1080p. This non-linear decline is typical of a GPU that is running out of fill rate and memory bandwidth at higher resolutions. The same pattern holds for High settings: 1080p High (95.6 FPS) to 1440p High (88.2 FPS) is a 7.7% drop, while 1440p High to 4K High (57.5 FPS) is a 34.8% drop. The difference between the 1080p-to-1440p and 1440p-to-4K drops is stark, indicating that the RX 6800 XT has ample headroom at 1080p and 1440p but begins to hit its limits at 4K. For Low settings, the scaling is even more revealing: 1080p Low (117.4 FPS) to 1440p Low (102.7 FPS) is a 12.5% drop, but 1440p Low to 4K Low (89.9 FPS) is only a 12.5% drop as well. This suggests that at Low settings, the CPU is starting to come into play at lower resolutions, but the GPU is still the primary limiter at 4K. The fact that 4K Low (89.9 FPS) is higher than 4K High (57.5 FPS) by 56% shows that the GPU’s shading units and texture units are heavily taxed by the higher quality settings. In summary, the data indicates that the i5-9400 is sufficient for this game at all resolutions, but the RX 6800 XT is the component that determines the final frame rate, especially at 4K where the 512.0 GB/s bandwidth is the bottleneck.

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

At 1920x1080, the system delivers its best performance. Low settings produce 117.4 FPS, which is the highest average in the entire dataset. Medium settings drop to 106.4 FPS, a 9.4% reduction from Low. High settings yield 95.6 FPS, and Ultra settings produce 94.6 FPS. The gap between High and Ultra is only 1%, suggesting that Ultra settings are not significantly more demanding than High at this resolution. The data shows that the RX 6800 XT is not stressed at 1080p, and the i5-9400 is capable of pushing over 100 FPS in most presets.

At 2560x1440, the frame rates remain high but start to show the GPU’s workload. Low settings produce 102.7 FPS, which is a 12.5% drop from 1080p Low. Medium settings hit 94.4 FPS, High settings reach 88.2 FPS, and Ultra settings drop to 83.3 FPS. The difference between 1080p and 1440p for each setting is roughly 10-12%, which is consistent with a GPU that is still well within its comfort zone. The 1440p Ultra figure of 83.3 FPS is still very playable, and the system is clearly not CPU-limited here.

At 3840x2160, the GPU becomes the clear bottleneck. Low settings produce 89.9 FPS, which is a 12.5% drop from 1440p Low. Medium settings drop to 70.3 FPS, High settings fall to 57.5 FPS, and Ultra settings bottom out at 54.5 FPS. The drop from 1440p High (88.2 FPS) to 4K High (57.5 FPS) is a 34.8% reduction, which is a significant hit. The Ultra preset at 4K is the only configuration that dips below 60 FPS, making it borderline for smooth gameplay. The data indicates that for 4K, users should stick to High or Medium settings to maintain a playable frame rate, as the gap between Medium (70.3 FPS) and High (57.5 FPS) is 22%.

FAQ

Q: Can the Intel Core i5-9400 handle Thief at 1080p with the RX 6800 XT?

A: Yes, the data shows the system achieves 117.4 FPS at 1080p Low and 95.6 FPS at 1080p High, indicating the CPU is not a bottleneck at this resolution.

Q: What is the best resolution for this combo to stay above 60 FPS?

A: At 1440p Ultra, the system produces 83.3 FPS, which is well above 60 FPS. At 4K, only Low (89.9 FPS) and Medium (70.3 FPS) settings stay above 60 FPS, while High (57.5 FPS) and Ultra (54.5 FPS) fall below.

Q: How does the RX 6800 XT compare to its nearest rival in terms of average benchmark score?

A: The RX 6800 XT has an average benchmark score of 49982, which is 0.5% higher than the Intel Arc A550M (49737) and 2.6% higher than the NVIDIA GeForce RTX 4070 Ti SUPER (48704).

Q: Is the i5-9400 a good match for the RX 6800 XT in this game?

A: Yes, the data shows that the GPU is the limiting factor at 4K, while the CPU provides enough headroom at 1080p and 1440p. The processor’s six cores are sufficient for Thief’s engine.

Q: What is the frame rate difference between Low and Ultra settings at 4K?

A: At 4K, Low settings produce 89.9 FPS, while Ultra settings produce 54.5 FPS. This is a 65% difference, showing that the GPU’s shading units are heavily taxed by higher quality presets.

Q: Does the RX 6800 XT have enough VRAM for Thief at 4K?

A: Yes, the 16 GB of GDDR6 memory is far more than the game requires, as Thief was released in 2014 and does not use high-resolution textures that would exceed even 8 GB of VRAM.

Settings Recommendations

For a smooth 60 FPS experience at 4K, the Medium preset is the best choice, delivering 70.3 FPS. This provides a 22% improvement over High settings (57.5 FPS) while still maintaining a visually acceptable level of detail for a 2014 title. If you prefer a higher frame rate, the Low preset at 4K offers 89.9 FPS, but the visual downgrade is substantial. At 1440p, the Ultra preset is the clear winner, producing 83.3 FPS, which is well above the 60 FPS threshold and offers the best visual fidelity. For 1080p, the High preset at 95.6 FPS is recommended, as the difference between High and Ultra (94.6 FPS) is only 1%, meaning you can save some GPU load without noticing a visual difference. The data suggests that the system is capable of running Thief at maximum settings at 1440p, but at 4K, users should compromise on settings to avoid dropping below 60 FPS. The Medium preset at 4K offers the best balance of visual quality and performance, as it maintains a playable frame rate while still retaining most of the game’s lighting and shadow effects. For competitive play or maximum smoothness, the 1440p Low preset at 102.7 FPS is the fastest configuration that still uses a reasonable resolution, but it sacrifices the game’s atmosphere. Overall, the RX 6800 XT is powerful enough to handle Thief at high settings at 1440p, but 4K requires a settings adjustment to keep the game fluid.