Roblox

Roblox, as a sandbox title built on a legacy engine, presents a unique benchmarking scenario. The pairing of an Intel Core i5-9400 with an AMD Radeon RX 6650 XT produces a dataset that is heavily skewed toward high frame rates, but the scaling between settings and resolutions reveals distinct bottlenecks. This analysis uses the measured data to interpret the performance envelope of this specific configuration.

Resolution Scaling

The measured FPS data shows a dramatic and predictable decline as resolution increases from 1920x1080 to 3840x2160. At 1920x1080 with Low settings, the configuration achieves an average of 322.1 FPS. Moving to 2560x1440 drops that figure to 212 FPS, a reduction of approximately 34%. The jump to 3840x2160 yields 119.1 FPS, which is a further 44% decline from the 1440p result. This pattern indicates that even at the lowest settings, the rendering load scales significantly with pixel count.

The scaling behavior changes when examining higher settings. At Ultra settings, the average FPS at 1920x1080 is 210.3. At 2560x1440, it falls to 136.3, and at 3840x2160, it bottoms out at 78.6 FPS. The percentage drop from 1080p to 4K at Ultra is roughly 63%, whereas the drop at Low settings is about 63% as well. The consistency of this relative decline suggests that the GPU is the primary limiting component across the board, as the frame rate scales inversely with the number of pixels being processed.

The data reveals that the gap between Low and Ultra settings narrows as resolution increases. At 1080p, the difference between Low (322.1 FPS) and Ultra (210.3 FPS) is 111.8 FPS. At 4K, the difference shrinks to 40.5 FPS (119.1 vs 78.6). This compression indicates that at higher resolutions, the pixel fill rate and memory bandwidth demands become more dominant, reducing the relative impact of the CPU-bound settings changes that affect geometry and draw calls. The i5-9400, with its six cores and six threads, appears sufficient to feed the GPU at lower resolutions but becomes less of a constraint as the GPU workload intensifies.

GPU Role

The AMD Radeon RX 6650 XT is the clear driver of the frame rates observed. Its 8 GB of GDDR6 memory on a 128-bit bus provides 280.3 GB/s of bandwidth, which is a critical resource for a game like Roblox that can have large, open worlds with many textures. The boost clock of 2635 MHz and game clock of 2410 MHz indicate the card is operating at high frequencies, and the benchmark results reflect this capability. The GPU's percentile rank of 72 among all GPUs places it in a strong position, but the nearest rivals data shows it is tightly clustered with the AMD Radeon RX 6800M (0% delta) and AMD Radeon RX 470 (0.1% delta), suggesting that its raw compute power is mid-pack in the broader landscape.

The memory bandwidth of 280.3 GB/s becomes a limiting factor at 4K Ultra, where the average FPS drops to 78.6. This is the lowest measured result in the entire dataset. The card's 64 ROPs and 128 TMUs are tasked with filling the 3840x2160 framebuffer, and the data shows that it can still maintain a playable frame rate, but the headroom is minimal. The shading units (2048) and the FP32 throughput of 10.79 TFLOPS are more than adequate for Roblox's relatively simple shaders, which is why the card can exceed 300 FPS at 1080p Low. The bottleneck at 4K is likely the memory subsystem and the pixel throughput, not the compute units.

Comparing the GPU to its nearest rivals, the RX 6650 XT's average benchmark score is 29024, which is nearly identical to the AMD Radeon RX 6800M (29011, 0% delta). This parity is interesting because the RX 6800M is a mobile part, but the data shows they perform equivalently in synthetic tests. The RX 6650 XT is also only 0.1% ahead of the older AMD Radeon RX 470, which indicates that generational improvements have not translated into a massive performance leap in this specific metric. For Roblox, the practical impact is that the card is capable of running the game at high frame rates in all measured scenarios, but the Ultra preset will stress the memory interface more than the compute cores.

FAQ

Q: What is the highest average FPS recorded for this configuration?

A: The highest average FPS is 322.1, achieved at 1920x1080 with Low settings.

Q: How does the 4K Ultra performance compare to the 1080p Low performance?

A: The 4K Ultra average is 78.6 FPS, which is only 24.4% of the 1080p Low average of 322.1 FPS. This shows a massive performance penalty for the highest resolution and quality settings.

Q: Is the CPU or GPU the primary bottleneck at 1080p Medium?

A: At 1080p Medium, the average FPS is 290.1. Given the high frame rate, the GPU is likely still the primary limiter, but the CPU's six-core design is sufficient to keep up with the frame rendering demands at this resolution.

Q: What is the difference in average FPS between 1440p High and 4K High?

A: The 1440p High average is 170.6 FPS, while the 4K High average is 94.6 FPS. This represents a 76 FPS drop, or about 44.6%, when moving to the higher resolution.

Q: Does the data suggest the RX 6650 XT is a strong performer for this game?

A: Yes. The GPU has a percentile rank of 72 against all GPUs, and its nearest rivals show it is within 0.6% of the AMD Radeon RX 6800M and the AMD Radeon RX 470. The measured results confirm it can handle Roblox at high frame rates across all tested settings.

Q: Which setting provides the most consistent frame rate relative to the resolution?

A: The Low preset shows the highest frame rates at every resolution, but the scaling from 1080p to 4K is the most severe, dropping from 322.1 to 119.1. The Medium preset offers a more balanced curve, with 290.1 FPS at 1080p and 107.7 FPS at 4K.

Settings Recommendations

Given the measured data, the optimal settings depend heavily on the target display resolution. For a 1920x1080 monitor, the Low preset at 322.1 FPS is ideal for competitive play or high refresh rate displays, but the Medium preset at 290.1 FPS offers a better visual experience with only a 9.9% performance penalty. The High preset at 259 FPS is also a strong candidate, providing a good balance of visual fidelity and frame rate. The Ultra preset at 210.3 FPS is the most demanding but still delivers a smooth experience for most users.

For 2560x1440, the Low preset at 212 FPS is the only one that exceeds the 200 FPS threshold. The Medium preset at 194.9 FPS is close, and the High preset at 170.6 FPS remains well above the 144 FPS refresh rate common on many monitors. The Ultra preset at 136.3 FPS is still playable but may not saturate a 144Hz panel. For this resolution, Medium or High is recommended to get the best combination of frame rate and visual quality, as the drop to Ultra only adds minor visual improvements for a 30% performance hit.

At 3840x2160, the situation is more constrained. The Low preset at 119.1 FPS is the only one that breaks the 100 FPS barrier. The Medium preset at 107.7 FPS is nearly identical, making it the better choice for 4K users who want better textures without sacrificing frame rate. The High preset at 94.6 FPS is still smooth for 60Hz displays, but the Ultra preset at 78.6 FPS is the least desirable, as the visual fidelity gains do not justify the substantial performance drop from the Medium preset. For 4K, Medium is the recommended preset, offering a respectable frame rate that is only 9.6% lower than Low.

Measured FPS Breakdown

At 1920x1080, the scaling across settings is linear. The Low preset yields 322.1 FPS, which is the peak performance for this configuration. The Medium preset drops to 290.1 FPS, a 9.9% reduction. High continues the trend with 259 FPS, a 10.7% drop from Medium. Ultra is the most demanding, delivering 210.3 FPS, which is 18.8% lower than High. The total spread from Low to Ultra is 111.8 FPS, showing that the settings have a significant impact on performance at this resolution.

Moving to 2560x1440, the same pattern emerges but with lower absolute numbers. Low remains the fastest at 212 FPS. Medium follows at 194.9 FPS, a reduction of 8.1%. High is next at 170.6 FPS, a 12.5% drop from Medium. Ultra trails at 136.3 FPS, which is 20.1% slower than High. The spread from Low to Ultra is 75.7 FPS, which is smaller than at 1080p, indicating that the GPU's pixel processing capabilities are becoming more of a factor.

At 3840x2160, the frame rates compress further. Low is still the top performer at 119.1 FPS. Medium is close behind at 107.7 FPS, showing only a 9.6% penalty. High drops to 94.6 FPS, a 12.2% reduction from Medium. Ultra is the slowest at 78.6 FPS, which is 16.9% below High. The spread from Low to Ultra is just 40.5 FPS, the smallest of any resolution. This confirms that at 4K, the GPU is fully saturated, and the differences between settings become less pronounced as the memory bandwidth and pixel fill rate become the primary constraints. The data shows a consistent hierarchy: Low is always fastest, followed by Medium, then High, with Ultra always slowest, but the relative gaps between them shrink as resolution increases.