Roblox

This system pairs a 6-core, 6-thread Intel Core i5-9400 with a 10 GB NVIDIA GeForce RTX 3080, a combination that spans very different performance tiers. The CPU sits near the middle of the database (47th percentile among all CPUs), while the GPU is much higher (68th percentile among all GPUs). For a sandbox game like Roblox, this creates an interesting balance, but the measured data reveals that the GPU is doing most of the heavy lifting, especially at higher resolutions. The recorded FPS numbers are exceptionally high across the board, with no preset or resolution dipping below 118 FPS average, which suggests the game is not a demanding title for this hardware. The following analysis breaks down what these measurements mean for actual gameplay, what settings to use, and how this combo compares to other tested configurations.

FAQ

Q: Can this PC run Roblox at 4K Ultra settings?

A: Yes, the data shows the combo achieves an average of 118.1 FPS at 3840x2160 with Ultra settings, which is well above the 60 FPS playable threshold.

Q: What is the best resolution to use with this hardware?

A: At 1920x1080, the combination reaches 312.7 FPS on Ultra, and at 2560x1440 it hits 211.6 FPS on Ultra. The 4K result of 118.1 FPS is still very smooth, so the choice depends on display capability rather than playability.

Q: How much performance difference is there between Low and Ultra settings at 1080p?

A: The recorded data shows 485.1 FPS on Low and 312.7 FPS on Ultra at 1920x1080, meaning Ultra reduces the average frame rate by about 35% compared to Low.

Q: Is the Intel Core i5-9400 a bottleneck for the RTX 3080 in this game?

A: The CPU is in the 47th percentile of all CPUs, while the GPU is in the 68th percentile. In Roblox, the FPS scales strongly with resolution, which indicates the GPU becomes more relevant at higher settings, but the CPU keeps up well enough to deliver over 300 FPS at 1080p.

Q: Does resolution scaling behave as expected for this combo?

A: Yes. Moving from 1920x1080 to 2560x1440 on Ultra drops the average from 312.7 to 211.6 FPS, and then to 118.1 FPS at 3840x2160. That is a consistent reduction as pixel count increases.

Q: What is the weakest setting for this game on this hardware?

A: The lowest recorded average is 118.1 FPS at 4K Ultra, which is still nearly double the 60 FPS threshold. No measured configuration falls below playable levels.

Best Settings per Resolution

The database records FPS for Low, Medium, High, and Ultra presets at three resolutions. The most demanding preset that stays at or above 60 FPS is Ultra in every case, since all presets clear that threshold by a wide margin.

At 1920x1080, Ultra settings yield an average of 312.7 FPS. This is the highest fidelity option and still delivers more than five times the playable threshold.

At 2560x1440, Ultra settings produce 211.6 FPS average. The gap between High (255.6 FPS) and Ultra is about 44 FPS, but both are far above 60.

At 3840x2160, Ultra settings average 118.1 FPS. The jump from Medium (166 FPS) to Ultra costs roughly 48 FPS, but the result remains comfortably above the playable mark.

In all cases, the recommendation is the same: run Ultra. The performance headroom is so large that there is no reason to reduce quality for frame rate stability.

CPU and GPU Roles

The data shows a clear pattern in how the CPU and GPU share the workload across resolutions. At 1920x1080, the combo reaches 485.1 FPS on Low settings, which is extremely high. When moving to Medium (436.6 FPS), High (389.5 FPS), and Ultra (312.7 FPS), the frame rate drops steadily. This suggests the CPU is capable of feeding the GPU at 1080p, but the GPU is not the limiting factor at the lowest preset.

At 2560x1440, the same pattern holds but with lower absolute numbers. Low hits 321.9 FPS, Medium 295.1 FPS, High 255.6 FPS, and Ultra 211.6 FPS. The reduction from 1080p to 1440p at Low settings is about 33%, which indicates the GPU is starting to take on more responsibility as the pixel count rises.

At 3840x2160, the scaling becomes more pronounced. Low averages 179.4 FPS, Medium 166 FPS, High 146.9 FPS, and Ultra 118.1 FPS. The difference between Low and Ultra at 4K is roughly 61 FPS, compared to a 172 FPS difference at 1080p. This narrowing gap shows that the GPU becomes the dominant factor at higher resolutions, while the CPU matters more at lower resolutions where the frame rate ceiling is higher.

The CPU percentile (47) is lower than the GPU percentile (68), yet the game still produces over 300 FPS at 1080p Ultra. This indicates that Roblox is not a heavily threaded title, and the i5-9400's six cores are sufficient even when paired with a much stronger GPU. At 4K, the GPU's capabilities (68th percentile) are more fully utilized, as evidenced by the 118.1 FPS Ultra result.

The Verdict

The recorded data makes the answer straightforward: this PC can run Roblox exceptionally well. The verdict by resolution confirms that all three resolutions (1920x1080, 2560x1440, and 3840x2160) have all four presets (Low, Medium, High, Ultra) listed as playable, meaning every configuration clears the 60 FPS threshold.

At 1080p, the best settings are Ultra with 312.7 FPS average. At 1440p, Ultra delivers 211.6 FPS. At 4K, Ultra still manages 118.1 FPS. No measured scenario falls below double the playable threshold. The lowest single data point in the entire set is the 4K Ultra result, which is still 97% above the 60 FPS minimum.

This is not a case where the user must compromise on visual quality to achieve smooth gameplay. The hardware is overpowered for this title, and the limiting factor would be the refresh rate of the display rather than the PC's capability. For a 60 Hz monitor, every setting is overkill. For a 144 Hz or 240 Hz display, the 1080p and 1440p results provide enough headroom for high-refresh gaming.

Similar Performance Alternatives

Looking at the nearest rivals in the database, the Intel Core i5-9400 has an average benchmark score of 2254. Its closest competitors are the Intel Core i7-1068NG7 (score 2259, delta -0.2%), the Intel Core i3-10305 (score 2264, delta -0.4%), the Intel Core i7-10710U (score 2248, delta 0.3%), and the AMD Ryzen 5 PRO 1500 (score 2246, delta 0.4%). These CPUs are all within a fraction of a percent of the i5-9400's performance, so swapping to any of them would yield nearly identical frame rates in Roblox. The differences are so small that they would be imperceptible in practice.

For the NVIDIA GeForce RTX 3080, the average benchmark score is 23172. The nearest rivals include the NVIDIA P106-100 (score 23249, delta -0.3%), the AMD Radeon Pro Vega 16 (score 23250, delta -0.3%), the AMD Radeon RX 6600M (score 23273, delta -0.4%), and the AMD Radeon R9 M290X (score 23276, delta -0.4%). Again, the performance deltas are below half a percent, meaning these GPUs would produce essentially the same FPS in Roblox. None of these alternatives would change the verdict: all configurations would still run the game at over 118 FPS average at 4K Ultra.

How This Combo Ranks

The combination of the Intel Core i5-9400 and the NVIDIA GeForce RTX 3080 ranks 1053 out of 3711 tested combos in the database for Roblox. That places it in the top 28% of all tested systems. This is a strong showing, especially considering the CPU is only in the 47th percentile overall. The high rank is driven almost entirely by the GPU's performance, which is in the 68th percentile.

The ranking suggests that most tested combos are either slower on the GPU side or paired with CPUs that do not meaningfully improve Roblox performance. Since the game runs this well even with a mid-tier CPU, the combo's position is more about GPU headroom than CPU strength. A faster CPU would likely not push the rank much higher, because the frame rates are already so far above the playable threshold.

Measured FPS Breakdown

The full set of recorded measurements shows consistent performance across all settings and resolutions.

At 1920x1080, the Low preset produces an average of 485.1 FPS. Medium increases the visual load and drops the average to 436.6 FPS. High settings yield 389.5 FPS, and Ultra brings the average down to 312.7 FPS. The step from Low to Ultra represents a 172.4 FPS reduction, but even the lowest value is over 300 FPS.

At 2560x1440, the averages are 321.9 FPS for Low, 295.1 FPS for Medium, 255.6 FPS for High, and 211.6 FPS for Ultra. The spread between Low and Ultra is 110.3 FPS, showing that resolution scaling has a larger impact than at 1080p.

At 3840x2160, the numbers are 179.4 FPS for Low, 166 FPS for Medium, 146.9 FPS for High, and 118.1 FPS for Ultra. The difference between Low and Ultra here is 61.3 FPS, which is the smallest absolute gap of any resolution. This indicates that at 4K, the GPU is the primary constraint, and preset changes have less relative impact than at lower resolutions.

No min or max FPS values are recorded in the database, so only the averages are available for analysis. All twelve data points are well above the 60 FPS playable threshold, with the lowest being 118.1 FPS at 4K Ultra. The data does not include any frame time measurements or 1% lows, so stutter behavior cannot be assessed from these numbers alone. However, given the high averages, any transient dips would still likely remain above playable levels.