Doom

The AMD Ryzen 7 5800X3D and Radeon RX 6600 XT combination delivers a compelling, if uneven, performance profile in Doom, a 2016 FPS that remains demanding at higher resolutions. The benchmark data shows a system that excels at high refresh-rate 1080p gaming but begins to show its limits as resolution climbs toward 4K, where the GPU becomes the primary bottleneck.

Resolution Scaling

The frame rate trajectory across resolutions reveals a classic GPU-bound scaling curve. At 1920x1080 with High settings, the combo produces 139.4 FPS. Moving to 2560x1440 High drops that to 91 FPS, a reduction of roughly 35%. The jump to 3840x2160 High yields just 48.1 FPS, another 47% cut from 1440p. This steep decline indicates that the Radeon RX 6600 XT is the limiting factor at higher pixel counts, while the CPU still has headroom to spare.

The scaling pattern is consistent across all settings. At Low, the system runs 189.6 FPS at 1080p, 121.4 FPS at 1440p, and 68.3 FPS at 4K. The gap between 1080p and 4K at Low settings is 121.3 FPS, a massive difference that underscores how pixel fill rate dominates performance. At Ultra, the same progression shows 116.7 FPS at 1080p, 73.5 FPS at 1440p, and 40.4 FPS at 4K. The 4K Ultra figure is barely playable, suggesting that this resolution/settings combination is beyond the card's comfortable range.

Notably, the drop from 1440p to 4K is steeper than the drop from 1080p to 1440p at every setting tier. This non-linear behavior is typical of a GPU where memory bandwidth and rasterization throughput become increasingly strained as pixel count quadruples. The 8 GB GDDR6 memory on a 128-bit bus with 256.0 GB/s bandwidth appears sufficient for 1080p and 1440p, but 4K pushes the card to its limits, particularly at higher detail presets.

How This Combo Ranks

In the database of tested CPU-GPU pairings for Doom, this configuration ranks 1248 out of 1681 combos. That places it in the lower third of all tested systems, which may seem surprising given the strong 1080p numbers. The ranking reflects the fact that many higher-end GPU pairings, particularly those with more powerful rasterization hardware, achieve far higher frame rates at 4K, dragging the average up.

The combo's position is heavily influenced by the RX 6600 XT's standing among GPUs. The card sits at the 71st percentile against all GPUs in aggregate benchmarks, with an average benchmark score of 27985. Its nearest rivals include the NVIDIA GeForce GTX 980 Ti, which scores nearly identically with a deltaPct of 0.1%, and the AMD Radeon R9 M395X at 0.4% ahead. More tellingly, the NVIDIA GeForce RTX 3070 is only 0.9% ahead in average score, yet in Doom the RTX 3070 would likely pull much further ahead at 4K due to its higher memory bandwidth and compute resources. The ranking also reflects the CPU's position: the Ryzen 7 5800X3D sits at the 83rd percentile among all CPUs, so the bottleneck is clearly the GPU.

At 1080p, the combo likely punches above its 1248 rank, as the CPU's strong single-thread performance can keep frame rates high. But the overall rank is dragged down by 4K results where the GPU cannot sustain competitive numbers. For a system targeting 1440p high-refresh gaming, this rank understates its capability; for 4K enthusiasts, it overstates it.

GPU Role

The Radeon RX 6600 XT, built on the RDNA 2.0 architecture with the Navi 23 chip, is the primary determinant of frame rates in this pairing. Its boost clock of 2589 MHz and game clock of 2359 MHz are high for a mid-range card, yet the 10.60 TFLOPS FP32 performance and 331.4 GTexel/s texture rate are modest by modern standards. The card features 2048 shading units, 128 TMUs, and 64 ROPs, which explains why it handles 1080p and 1440p well but struggles at 4K.

The 8 GB GDDR6 memory with a 128-bit bus width produces 256.0 GB/s of bandwidth. This is adequate for Doom's texture-heavy environments at 1080p and 1440p, where the measured FPS shows no signs of memory capacity issues. However, at 4K Ultra, the 40.4 FPS result suggests that both bandwidth and capacity are strained. The card's pixel rate of 165.7 GPixel/s is a hard ceiling for 4K output; at 3840x2160, filling 8.3 million pixels per frame at 60 FPS requires nearly 500 GPixel/s, far beyond what this GPU can deliver.

The GPU's percentile ranking of 71 places it above average, but the nearest rival data shows how tight the mid-range is. The GTX 980 Ti's average score of 27956 is just 0.1% below, meaning the RX 6600 XT offers comparable raw compute in synthetic tests. Yet in Doom, the newer architecture's features like DirectX 12 Ultimate and Vulkan 1.4 support may yield better real-world results than the raw scores suggest. The card's 64 ROPs are a limiting factor for 4K, as are the 32 ray tracing cores, which are unused in this title but indicate the card's modern feature set.

Measured FPS Breakdown

At 1920x1080, the system delivers excellent performance across all settings. Low settings produce 189.6 FPS, Medium hits 165 FPS, High achieves 139.4 FPS, and Ultra manages 116.7 FPS. The spread from Low to Ultra is 72.9 FPS, showing that the GPU can absorb significant detail increases while staying above 100 FPS. This makes the combo ideal for high-refresh-rate 1080p monitors, even at maximum detail.

At 2560x1440, the frame rates remain playable but with a clearer settings impact. Low yields 121.4 FPS, Medium drops to 110 FPS, High settles at 91 FPS, and Ultra falls to 73.5 FPS. The 47.9 FPS spread between Low and Ultra is smaller than at 1080p, indicating the GPU is becoming the limiting factor. The 1440p High result of 91 FPS is smooth for most displays, while Ultra at 73.5 FPS is still acceptable for slower-paced sections.

At 3840x2160, the card's limitations are evident. Low produces 68.3 FPS, Medium 60 FPS, High 48.1 FPS, and Ultra 40.4 FPS. The Low setting is the only one that maintains a comfortable frame rate, while Ultra dips below 45 FPS, which many players would find choppy. The difference between 1080p Low and 4K Low is 121.3 FPS, while the difference between 1080p Ultra and 4K Ultra is 76.3 FPS, showing that higher settings compress the resolution gap slightly but never make 4K viable.

CPU Role

The AMD Ryzen 7 5800X3D, with 8 cores and 16 threads based on Zen 3 architecture, is more than capable of feeding the RX 6600 XT in Doom. Its base clock of 3.40 GHz and boost clock of 4.50 GHz are supplemented by a massive 96 MB shared L3 cache, which is the processor's standout feature. This cache size is crucial for gaming, as it reduces memory latency and improves frame pacing in CPU-bound scenarios.

The CPU's benchmark results confirm its strength. In Cinebench R23, it scores 24063 in multi-core and 3397 in single-core, placing it in the top tier for gaming CPUs. Its Geekbench single-core score of 2116 and multi-core score of 11061 further validate its capability. The 3DMark scores show a clear scaling pattern: 1746 at 2 threads, 3392 at 4 threads, 5906 at 8 threads, and 7299 at 16 threads. This near-linear scaling indicates the CPU can handle fully threaded workloads, though Doom is unlikely to use all 16 threads.

The CPU's percentile ranking of 83 against all CPUs, with an average benchmark score of 26574, places it near the Intel Core i9-11900K, which scores 26546 with a deltaPct of 0.1%. The AMD Ryzen 5 7600 is 0.2% ahead, and the Intel Core i9-12900HK is 0.4% ahead. This clustering shows the 5800X3D is competitive with modern mid-range and previous-gen high-end chips, but its real advantage in Doom is the L3 cache, which the benchmark scores do not fully capture.

In this game, the CPU is rarely the bottleneck. At 1080p Low, the 189.6 FPS result is likely near the CPU's maximum frame rate capability, as the GPU has enough headroom to let the processor stretch. But at 1440p and 4K, the GPU's rendering limits dominate, and the CPU's role diminishes. The 105W TDP and dual-channel DDR4 memory support are standard, and the PCIe Gen 4 interface with 20 lanes provides sufficient bandwidth for the GPU's x8 connection. The CPU's 51.2 GB/s memory bandwidth is adequate for the game's data streaming, though the 96 MB cache likely reduces reliance on system memory.