Roblox

Roblox is a deeply CPU-bound sandbox title, and the benchmark results for the Intel Core i5-9400 + AMD Radeon RX 580 combo reflect that dynamic clearly. The data shows this pairing is capable of delivering high frame rates at 1080p, but performance degrades significantly as resolution increases, revealing the RX 580 as the primary bottleneck in more demanding scenarios. The combination ranks at 1686 out of 1800 tested combos in this game, placing it in the lower-middle tier of the database, yet its measured FPS numbers indicate that it remains a thoroughly playable setup for the vast majority of Roblox's content.

CPU Role

The Intel Core i5-9400 is a 6-core, 6-thread processor from the Coffee Lake architecture, running on a 14 nm process. Its base clock is 2.90 GHz, which can boost up to 4.10 GHz, and it features a 9 MB shared L3 cache. In the context of Roblox, this CPU is the dominant force. The game relies heavily on single-threaded physics and game logic, making the i5-9400's boost clock particularly relevant. The benchmark data supports this: at 1080p, the combo achieves 164.8 FPS on Low settings, a figure that is only slightly reduced to 129.9 FPS on High settings. This relatively small drop between settings presets at the same resolution suggests the CPU is capable of feeding the GPU with enough data, but the GPU becomes the limiting factor as graphical load increases.

The i5-9400's synthetic benchmark scores place it at the 50th percentile among all CPUs, with an average benchmark score of 2305. Its nearest rivals are the Intel Core i3-10305 (deltaPct 0.2), Intel Core i3-1125G4 (deltaPct 0.2), and Intel Xeon E-2134 (deltaPct 0.4), all of which are within a fraction of a percent in performance. It trails the Intel Core i7-8809G by a 0.6% margin. This indicates that the i5-9400 sits in a tightly contested performance band, but its 6 cores and 6 threads are more than adequate for Roblox's typical workload, which rarely scales beyond a few threads. The lack of hyper-threading is not a measurable detriment in this specific game, as the frame rate data shows no signs of CPU saturation at 1080p.

GPU Role

The AMD Radeon RX 580 is a Polaris 20 chip built on GCN 4.0 architecture, using a 14 nm process. It comes with 8 GB of GDDR5 memory on a 256-bit bus, delivering 256.0 GB/s of bandwidth. The GPU has a base clock of 1257 MHz and a boost clock of 1340 MHz, with 2304 shading units and 32 ROPs. In Roblox, the GPU's role is to render the simpler, stylized graphics at high frame rates. The 8 GB VRAM is more than sufficient for this game, even at 4K, as Roblox's textures and geometry are not memory-intensive. The benchmark results confirm that the RX 580 is not VRAM-limited here; instead, its raw compute throughput is what gets taxed.

The RX 580 holds a 53rd percentile ranking among all GPUs, with an average benchmark score of 13559. Its nearest rival is the NVIDIA GeForce GTX 570 with a deltaPct of 0, meaning they perform nearly identically in synthetic tests. It also edges out the GeForce GTX 950 (deltaPct 0.1) and AMD Radeon Pro 455 (deltaPct 1.1), but lags behind the NVIDIA P106-090 by 1.1%. At 1080p, the GPU is able to push frame rates well above 100 FPS in most settings, but the transition to 4K shows a steep drop. At 4K Ultra, the combo only manages 39.3 FPS, indicating that the GPU's 6.175 TFLOPS of FP32 compute is being fully utilized, and it cannot keep up with the pixel count, making it the clear performance limiter at that resolution.

Resolution Scaling

The data reveals a predictable pattern where the limiting component shifts from CPU to GPU as resolution increases. At 1920x1080, the combo delivers 164.8 FPS on Low, 148.6 FPS on Medium, 129.9 FPS on High, and 105.8 FPS on Ultra. These numbers are high, and the spread between Low and Ultra is only about 59 FPS, suggesting the CPU is doing the heavy lifting to maintain a high baseline. Moving to 2560x1440, the frame rates drop to 111.6 FPS (Low), 102.4 FPS (Medium), 86.7 FPS (High), and 72.5 FPS (Ultra). The drop from 1080p to 1440p is roughly 32% across the board, indicating the GPU is starting to take on more work.

The most telling shift occurs at 3840x2160. Here, the combo drops to 60.8 FPS on Low, 54.2 FPS on Medium, 52.9 FPS on High, and 39.3 FPS on Ultra. The gap between Low and Ultra at 4K is 21.5 FPS, and the absolute values are much lower. The 4K Low setting is the only one that stays above 60 FPS, and it does so barely. This pattern clearly shows that the RX 580's pixel throughput is the bottleneck at 4K. The CPU is no longer the constraint; the GPU is struggling to fill the additional pixels, resulting in a 64% performance drop from 1080p Low to 4K Low. This is a classic sign of a GPU-bound scenario at higher resolutions.

How This Combo Ranks

In the overall benchmark database for Roblox, this combo ranks 1686 out of 1800 combinations, placing it in the bottom 7% of tested systems. This low ranking is primarily due to the age of the components, but it should be interpreted with context. The ranking reflects a broad swath of modern hardware, including top-tier CPUs and GPUs that are significantly more powerful. However, the measured FPS data shows that this combo is far from unplayable. At 1080p, it achieves frame rates that are suitable for competitive play, and even at 1440p, it maintains playable numbers. The ranking is a relative measure, not an absolute verdict on usability.

The data indicates that the combo is well-balanced for 1080p gaming, but it falls behind when compared to more modern pairings. The synthetic benchmark scores for the individual components support this: the CPU is at the 50th percentile, and the GPU is at the 53rd percentile. When combined, they do not synergize to climb above their individual standings in this specific game. The low rank is likely because Roblox is heavily CPU-dependent, and while the i5-9400 is adequate, it is not exceptional. The ranking suggests that users with this combo are getting exactly what the individual parts promise, no more and no less.

Measured FPS Breakdown

The measured FPS data provides a comprehensive view of performance across all resolutions and settings. At 1920x1080, the combo performs admirably: Low settings yield 164.8 FPS, Medium 148.6 FPS, High 129.9 FPS, and Ultra 105.8 FPS. These numbers are all well above the 60 FPS threshold, making 1080p the sweet spot for this hardware. The scaling is smooth, with each settings step reducing the frame rate by a reasonable margin.

At 2560x1440, performance remains solid but begins to show strain. Low settings deliver 111.6 FPS, Medium 102.4 FPS, High 86.7 FPS, and Ultra 72.5 FPS. The Ultra setting is still playable, but the gap between Low and Ultra has widened to 39.1 FPS, indicating the GPU is becoming more relevant. At 3840x2160, the frame rates drop significantly: Low yields 60.8 FPS, Medium 54.2 FPS, High 52.9 FPS, and Ultra 39.3 FPS. Here, only the Low setting achieves a consistent 60 FPS, while Ultra is choppy and best avoided. The data shows a clear trend: the combo is best suited for 1080p gaming, is acceptable at 1440p with settings adjustments, and is only marginally playable at 4K on the lowest settings.

FAQ

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

A: The data shows that 1920x1080 is the optimal resolution, with all settings presets delivering frame rates above 100 FPS. The highest measured value is 164.8 FPS on Low, and even the most demanding Ultra preset achieves 105.8 FPS.

Q: Can this combo handle 4K gaming in Roblox?

A: It can, but with limitations. At 3840x2160, the combo only manages 60.8 FPS on Low settings. Medium, High, and Ultra settings all fall below 60 FPS, with Ultra dropping to 39.3 FPS.

Q: How does the RX 580 compare to its closest rivals?

A: The RX 580 has an average benchmark score of 13559, which is essentially tied with the NVIDIA GeForce GTX 570 (deltaPct 0). It is 0.1% faster than the GeForce GTX 950 and 1.1% faster than the AMD Radeon Pro 455, but 1.1% slower than the NVIDIA P106-090.

Q: Is the CPU or GPU the limiting factor at 1080p?

A: The data suggests the CPU is the primary driver at 1080p. The frame rate difference between Low and Ultra settings is only 59 FPS, indicating that the GPU is not being fully stressed. The CPU's 4.10 GHz boost clock is sufficient to maintain high frame rates.

Q: What is the combo's overall rank in the database?

A: The combo ranks 1686 out of 1800 tested combinations in Roblox. This places it in the lower tier of performance, but the measured FPS shows it remains adequate for standard gaming.

Q: How much VRAM does the GPU have, and is it enough?

A: The RX 580 has 8 GB of GDDR5 memory. In Roblox, this is more than sufficient, as the game's assets are not memory-intensive. The measured FPS data does not indicate any VRAM-related stuttering or performance loss.

Settings Recommendations

Based on the measured FPS rows, the optimal settings depend on the user's priority for frame rate versus visual fidelity. For a smooth and responsive experience, the 1080p Medium preset is the best balance, delivering 148.6 FPS. This is a significant jump from the 129.9 FPS on High, while still offering improved visuals over Low. If the user has a 1440p monitor, the Low preset is the safest choice at 111.6 FPS, as it remains well above 60 FPS; the Medium preset at 102.4 FPS is also viable. For 4K, the Low preset is the only one that maintains a playable 60.8 FPS, but users should expect a less detailed image.

For users who prioritize visual quality over frame rate, the 1080p Ultra preset at 105.8 FPS is still smooth enough for most gameplay. However, the 1440p Ultra preset at 72.5 FPS is the highest visual fidelity that remains comfortably playable. The 4K Ultra preset at 39.3 FPS is not recommended for any serious gameplay, as it is below the 60 FPS threshold and will feel sluggish. Ultimately, the data suggests that this combo is best utilized at 1080p with High or Ultra settings, or at 1440p with Low or Medium settings, to ensure a consistent frame rate above 60 FPS.