Roblox

Roblox is a sandbox title that rarely stresses high-end hardware in the way a AAA shooter does, but the data for this specific pairing of an Intel Core i5-9400 and an AMD Radeon RX 7900 XT reveals a fascinating bottleneck dynamic. The benchmark results show a system that is overwhelmingly capable of delivering high frame rates, yet the performance scaling across resolutions and settings indicates that the CPU is the primary limiter in most scenarios. This combination ranks 410th out of 1800 tested combos, placing it in the top quarter of all configurations, which is a strong showing for a CPU that sits at the 50th percentile against all processors.

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

The Intel Core i5-9400 is a six-core, six-thread processor based on the Coffee Lake architecture, built on a 14 nm process. It has a base clock of 2.90 GHz and a boost clock of 4.10 GHz, with a 9 MB shared L3 cache. Its benchmark scores are modest; it achieves a Cinebench R23 multicore score of 7969 and a single-core score of 1125. In the broader landscape, this CPU sits at the 50th percentile of all processors, with an average benchmark score of 2305. Its nearest rivals are tightly clustered; the Intel Core i3-10305 and Intel Core i3-1125G4 are virtually identical, with scores of 2300 and 2299, respectively, representing a delta of just 0.2%. The Intel Xeon E-2134 is also close at 2295 (0.4% slower), while the Intel Core i7-8809G is slightly faster at 2319 (0.6% faster).

In Roblox, the impact of this CPU is most evident in the frame rate ceilings observed at lower resolutions. The data shows that at 1080p, the average FPS ranges from 352.5 on Ultra settings to 541.4 on Low settings. This massive spread—a jump of over 188 FPS between the highest and lowest settings—indicates that the CPU is not the limiting factor at these settings; instead, the GPU is being fed more work as settings increase, which lowers the framerate. However, the fact that even the lowest 1080p score (352.5 FPS) is so high suggests that the six cores are sufficient to push Roblox to extreme levels. The single-threaded performance, while not elite, is adequate for a game that often relies on a single main simulation thread. The real story emerges when comparing 1080p to 1440p; the FPS drops from 433.2 to 293.0 on High settings, a reduction of about 32%. This drop is more attributable to the GPU's workload, but the CPU's six threads without hyper-threading could still be a constraint in heavily populated scenes, though the data does not explicitly test that scenario.

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

The AMD Radeon RX 7900 XT is a flagship-class GPU from the RDNA 3.0 architecture, built on a 5 nm process. It features 20 GB of GDDR6 memory on a 320-bit bus, delivering 800.0 GB/s of bandwidth. Its boost clock is 2394 MHz, with a game clock of 2025 MHz. The GPU has 5376 shading units and 192 ROPs. Its raw compute power is significant, with an FP32 throughput of 51.48 TFLOPS. The GPU sits at the 82nd percentile of all GPUs, with an average benchmark score of 38358. Its nearest rivals are extremely close; the NVIDIA GeForce RTX 5080 Mobile matches its score at 38349 (0% delta), and the NVIDIA CMP 70HX is just 0.3% slower at 38225. The NVIDIA GeForce RTX 4080 Mobile is 0.6% slower at 38135, while the NVIDIA GeForce MX570 is slightly faster at 38494 (0.4% faster).

In Roblox, the GPU's role is primarily to push higher resolutions and visual fidelity. The data shows that at 4K (3840x2160), the average FPS on High settings is 166.9, which is a very playable number. However, at 1080p, the GPU is often bottlenecked by the CPU, as evidenced by the relatively small difference between Low (541.4 FPS) and Medium (493.3 FPS) settings. The GPU's 20 GB VRAM is far more than Roblox needs, meaning VRAM capacity is not a concern. The real constraint at 4K is the GPU's compute power; the drop from 206.6 FPS on Low to 132.3 FPS on Ultra at 4K shows a 36% performance hit, which is a clear indication that the GPU is being fully utilized at this resolution. The RX 7900 XT is so powerful that it is only at 4K Ultra that the GPU starts to become the primary limiter, whereas at 1080p, the CPU's six cores cap the potential frame rates.

FAQ — 4-6 Q&A pairs answerable from FACT PACK data

Q: What is the highest average FPS this combo achieves at 1080p?

A: The highest average FPS at 1080p is 541.4, observed on Low settings. This is a stark contrast to the 352.5 FPS on Ultra settings, showing a 188.9 FPS spread due to GPU workload scaling.

Q: How does this combo's CPU compare to its nearest rival?

A: The Intel Core i5-9400 has an average benchmark score of 2305. Its closest rival, the Intel Core i3-10305, scores 2300, which is a 0.2% difference. The Intel Core i7-8809G is slightly faster at 2319, a -0.6% delta.

Q: Is the GPU or CPU the limiting factor at 1440p?

A: At 1440p with High settings, the average FPS is 293.0. Since this is lower than the 1080p High score of 433.2, the GPU is becoming a more significant factor, but the CPU is still not fully saturated, as the FPS remains well above 240.

Q: What is the combo's overall rank among all tested configurations?

A: The combo ranks 410th out of 1800 tested combos in Roblox. This places it in the top 22.8% of all systems tested, which is a strong result for a CPU that is only at the 50th percentile.

Q: How much does the FPS drop from 1080p to 4K on Ultra settings?

A: On Ultra settings, the average FPS drops from 352.5 at 1080p to 132.3 at 4K. This represents a 62.5% reduction in performance, indicating that the GPU is heavily loaded at 4K.

Q: What is the GPU's average benchmark score and percentile?

A: The AMD Radeon RX 7900 XT has an average benchmark score of 38358 and sits at the 82nd percentile of all GPUs. Its nearest rival, the NVIDIA GeForce RTX 5080 Mobile, scores 38349, a negligible 0% difference.

How This Combo Ranks — use comboRankInGame vs other tested combos

The combination of the Intel Core i5-9400 and the AMD Radeon RX 7900 XT achieves a rank of 410 out of 1800 tested combos in Roblox. This puts the system in the 77th percentile of all configurations, meaning it outperforms more than three-quarters of the other tested setups. Given that the CPU is at the 50th percentile, this high ranking is almost entirely due to the GPU's performance, which is at the 82nd percentile. The data suggests that the RX 7900 XT is carrying the combo in Roblox, especially at higher resolutions where its 20 GB VRAM and 800.0 GB/s bandwidth come into play. However, the ranking also indicates that there are 409 other combos that perform better, likely those with newer CPUs that can better feed the GPU at lower resolutions. The 410th rank is a reminder that while this is a capable system, it is not top-tier, and the CPU is a limiting factor in extracting the absolute maximum FPS from the GPU.

Resolution Scaling — how FPS drops from 1080p to 4K and what it says about the limiting component

The scaling of average FPS across resolutions reveals a clear picture of where the bottleneck lies. At 1080p, the system is heavily CPU-bound; the average FPS on High settings is 433.2, and even at Ultra, it is 352.5. These numbers are far above what the GPU would be capable of if it were the sole limiter, indicating that the CPU's six cores are capping performance. Moving to 1440p, the FPS drops to 293.0 on High and 234.1 on Ultra, which is a reduction of about 32% and 34%, respectively. This drop indicates that the GPU is starting to take on more work, but the CPU is still not the bottleneck, as the scores remain high. At 4K, the pattern changes dramatically; the FPS on High drops to 166.9 and on Ultra to 132.3. This represents a 61.5% drop from 1080p to 4K on High settings, and a 62.5% drop on Ultra. This steep decline shows that the GPU is now the primary limiter, as it is fully saturated with the increased pixel count. The data suggests that 1080p and 1440p are CPU-limited, while 4K is GPU-limited. This is a classic sign of an older CPU paired with a modern, high-end GPU; the CPU can handle the game's logic at lower resolutions, but the GPU's raw power is only fully utilized at 4K.

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

1080p (1920x1080):

• Low: 541.4 avg FPS
• Medium: 493.3 avg FPS
• High: 433.2 avg FPS
• Ultra: 352.5 avg FPS

The spread between Low and Ultra is 188.9 FPS, showing that the GPU is doing more work as settings increase, but the CPU is still able to keep up, as all scores are above 350 FPS.

1440p (2560x1440):

• Low: 361.1 avg FPS
• Medium: 329.4 avg FPS
• High: 293.0 avg FPS
• Ultra: 234.1 avg FPS

The gap between Low and Ultra narrows to 127.0 FPS, indicating that the GPU is becoming more of a factor, but the CPU is still not the primary constraint, as even the lowest score (234.1) is high.

4K (3840x2160):

• Low: 206.6 avg FPS
• Medium: 185.2 avg FPS
• High: 166.9 avg FPS
• Ultra: 132.3 avg FPS

The spread here is 74.3 FPS, the smallest of all resolutions. This is a clear indication that the GPU is now the bottleneck; the RX 7900 XT is working hard to render at 4K, and the CPU has headroom. The 4K Ultra score of 132.3 FPS is still very playable, but it is a far cry from the 541.4 FPS at 1080p Low. This data confirms that for Roblox, this combo is best suited for high-refresh-rate 1440p gaming, where it can consistently exceed 230 FPS on Ultra, or for 4K gaming where it remains above 130 FPS on the highest settings.