Fortnite

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

The measured FPS data for this Fortnite configuration reveals a steep and consistent performance cliff as resolution climbs. At 1080p with Low settings, the combo averages 115 FPS. Moving to 1440p Low drops that to 73 FPS, a 36% reduction, and at 4K Low the average falls to 39 FPS, which is 66% below the 1080p figure. This pattern — where doubling pixel count roughly halves frame rates — is the classic signature of a GPU-bound scenario. The Intel Arc B390 is the constraining factor here, not the CPU.

The scaling behavior across settings tells the same story. At 1080p Medium, the average is 81 FPS; at 1440p Medium it drops to 51 FPS; at 4K Medium it falls to 27 FPS. The gap between Low and Medium at each resolution is relatively modest (roughly 30% at 1080p, 30% at 1440p, and 31% at 4K), which indicates that the GPU is already near its ceiling even at the lowest quality preset. When you push to Ultra, the numbers crater: 41 FPS at 1080p, 26 FPS at 1440p, and just 14 FPS at 4K. The 4K Ultra result is essentially unplayable for a competitive shooter, and even 1080p Ultra falls below the 60 FPS threshold that most Fortnite players target.

What this tells a builder is straightforward: if you pair a Ryzen 5 3600 with an Arc B390, you are buying a 1080p-oriented machine. The data shows that 1440p is only viable on Low settings, and 4K is not a realistic option for smooth gameplay at any quality level. The CPU has headroom to spare — the 3600's 6 cores and 12 threads are more than adequate for Fortnite's workload — but the GPU's 7.680 TFLOPS of FP32 compute and 24 ROPs simply cannot keep up with higher pixel counts. The bottleneck is unambiguous.

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

The Intel Arc B390 is an integrated graphics solution built on the Xe3-LPG architecture, manufactured on Intel's 3 nm process. Its memory configuration is "System Shared" — meaning it draws from the system's DDR4 RAM rather than dedicated VRAM — with bandwidth listed as "System Dependent." This is a critical detail for Fortnite, a game that benefits from fast memory access. The Ryzen 5 3600's dual-channel DDR4 provides 51.2 GB/s of bandwidth, which is shared between the CPU and the iGPU. That shared bandwidth explains why the GPU's 3DMark Steel Nomad DX12 score of 1482 places it in the 9th percentile of all GPUs, with nearest rivals being the GeForce GT 520MX (1463, 1.3% ahead) and GeForce 800M (1460, 1.5% ahead).

Clock speeds are modest: a 300 MHz base and 2500 MHz boost. The boost clock is what matters during gaming, and it is respectable for an integrated part, but the 1536 shading units and 48 TMUs are the limiting factors. The pixel rate of 60.00 GPixel/s and texture rate of 120.0 GTexel/s are low for modern standards. Fortnite's stylized art style is not as demanding as photorealistic titles, but at 4K Ultra the game's draw distance and shadow effects overwhelm these specs. The 12 RT cores are present, but Fortnite's ray-traced features are not the primary load — the raw rasterization work is what drags the frame rate to 14 FPS at 4K Ultra.

The data shows that the GPU's performance is consistent with its low percentile ranking. At 1080p Low, the 115 FPS average is playable, but the 9th percentile placement means this is a component for esports-level settings, not eye candy. The 80 W TDP and IGP slot width (no power connectors needed) indicate this is a low-power, low-performance solution. For Fortnite specifically, the GPU's lack of dedicated VRAM means texture quality is the first casualty — High settings at 1080p yield 63 FPS, which is acceptable, but Medium at 81 FPS is the practical sweet spot for maintaining frame time consistency.

FAQ

Q: Can this combo run Fortnite at 1080p with competitive settings?

A: Yes. At 1080p Low, the average FPS is 115, and at Medium it is 81 FPS. Both are above the 60 FPS threshold for smooth play. High settings drop to 63 FPS, which is still playable but leaves less headroom for intense build fights or storm circles.

Q: What is the best resolution for this setup?

A: The data clearly favors 1080p. At 1440p, only Low settings (73 FPS) approach playable levels; Medium drops to 51 FPS. At 4K, even Low (39 FPS) is below the 60 FPS standard. Stick to 1080p for any competitive play.

Q: How does the Arc B390 compare to its nearest GPU rivals?

A: The GPU's 3DMark Steel Nomad score of 1482 puts it just ahead of the GeForce GT 520MX (1463, +1.3%) and GeForce 800M (1460, +1.5%), and further ahead of the GT 625 OEM (1446, +2.5%) and GT 710 (1443, +2.7%). These are all entry-level parts from previous generations.

Q: Is the Ryzen 5 3600 holding back the GPU?

A: No. The CPU's benchmark scores — including a Cinebench R23 multi-core result of 15045 and single-core of 2124 — indicate it has ample processing power for Fortnite. The 71st percentile ranking among all CPUs shows it is a mid-range part, but the GPU's 9th percentile ranking is the clear bottleneck.

Q: What frame rate can I expect at 4K with this combo?

A: Poor results across the board. Low settings yield 39 FPS, Medium 27 FPS, High 21 FPS, and Ultra 14 FPS. None of these are acceptable for a fast-paced Battle Royale game. 4K is not viable with this hardware.

Q: Does the shared memory configuration hurt performance in Fortnite?

A: Yes, indirectly. The GPU uses system memory with bandwidth dependent on the CPU's DDR4 setup (51.2 GB/s dual-channel). This is far slower than dedicated GDDR6 VRAM, which explains why texture-heavy settings like High and Ultra cause steep frame rate drops.

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

The measured FPS data for Fortnite with the Ryzen 5 3600 and Arc B390 is as follows:

1920x1080 (1080p)

• Low: 115 FPS average
• Medium: 81 FPS average, with a minimum of 69 FPS and maximum of 93 FPS
• High: 63 FPS average
• Ultra: 41 FPS average

2560x1440 (1440p)

• Low: 73 FPS average
• Medium: 51 FPS average, with a minimum of 44 FPS and maximum of 59 FPS
• High: 40 FPS average
• Ultra: 26 FPS average

3840x2160 (4K)

• Low: 39 FPS average
• Medium: 27 FPS average, with a minimum of 23 FPS and maximum of 31 FPS
• High: 21 FPS average
• Ultra: 14 FPS average

The Medium settings at each resolution include min/max data, which is useful for understanding frame time consistency. At 1080p Medium, the range from 69 to 93 FPS shows a 24 FPS spread — noticeable but manageable. At 1440p Medium, the spread narrows to 44-59 FPS (15 FPS range), and at 4K Medium it tightens further to 23-31 FPS (8 FPS range). This pattern indicates that as the GPU becomes more saturated, frame times become more consistent but at a much lower average. In competitive terms, the 1080p Medium result is the only one that offers both playable averages and acceptable variance.

The jump from Medium to High at each resolution is significant: 18 FPS at 1080p (81 to 63), 11 FPS at 1440p (51 to 40), and 6 FPS at 4K (27 to 21). The diminishing absolute drops at higher resolutions reflect the GPU's inability to handle the added detail, regardless of the quality preset. Ultra settings are uniformly bad — even at 1080p, the 41 FPS average would put a player at a severe disadvantage in build fights.

How This Combo Ranks — use comboRankInGame vs other tested combos

In the database of tested CPU-GPU combinations for Fortnite, this pairing ranks 2417 out of 2740 combos. That places it in the bottom 12% of all tested configurations. This is a low ranking, but it is not surprising given the GPU's 9th percentile standing among all GPUs. The CPU's 71st percentile ranking suggests that the combo's poor position is almost entirely attributable to the Arc B390.

The rank of 2417 means that roughly 323 other combos performed worse in Fortnite. Those are likely older or lower-end integrated graphics solutions or severely mismatched pairings. However, the vast majority of tested combos — over 2400 of them — deliver better frame rates in this game. This is a significant finding for anyone considering this hardware: while the combo technically runs Fortnite, it does so at a level that most other tested systems surpass.

For context, the CPU's nearest rivals in synthetic benchmarks — the Intel Core i7-1260P (avg score 17007, +0.2%), Intel Core i5-11400 (17067, -0.2%), AMD EPYC 7573X (17070, -0.2%), and AMD EPYC 7742 (16998, +0.2%) — all have similar CPU performance. If any of those CPUs were paired with a stronger GPU, the combo rank would improve dramatically. The data suggests that the Arc B390 is the limiting factor, and upgrading the GPU alone would yield a substantially better rank.

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

The AMD Ryzen 5 3600 is a 6-core, 12-thread processor based on the Zen 2 architecture (codenamed Matisse), manufactured on TSMC's 7 nm process. Its base clock is 3.60 GHz with a boost clock of 4.20 GHz. The CPU has a 65 W TDP and supports dual-channel DDR4 memory with 51.2 GB/s bandwidth. Its 32 MB of shared L3 cache is beneficial for gaming workloads that require frequent data access.

In Fortnite, the CPU's role is to handle game logic, physics calculations, and draw call processing, while the GPU handles rendering. The 3600's benchmark results show it is more than capable of this task. Its 3DMark single-thread score of 696 and multi-thread score of 4603 (max threads) indicate solid per-core performance. The Cinebench R23 results — 2124 single-core and 15045 multi-core — place it comfortably in the mid-range tier. The PassMark single-thread score of 2562 and multi-thread score of 17700 further confirm this.

The data shows that at 1080p Low, where the GPU has less work to do, the combo achieves 115 FPS. This is a CPU-friendly scenario, but the 3600 does not become the bottleneck even here — the GPU still limits performance. At higher resolutions, the CPU's utilization likely decreases as the GPU struggles to keep up. The 6 cores and 12 threads are sufficient for Fortnite's engine, which is not heavily multi-threaded compared to other Battle Royale titles.

The CPU's 71st percentile ranking among all CPUs, with an average benchmark score of 17035, places it just behind the Intel Core i5-11400 (17067, -0.2%) and AMD EPYC 7573X (17070, -0.2%), and just ahead of the Intel Core i7-1260P (17007, +0.2%) and AMD EPYC 7742 (16998, +0.2%). These are all comparable performers, which reinforces that the CPU is not the weak link in this combo. If you were to keep the Ryzen 5 3600 and swap in a more powerful discrete GPU, the Fortnite frame rates would improve substantially, as the CPU has headroom to feed a faster graphics card.