AMD Radeon RX 550X vs AMD Radeon RX 6600S Comparison

The AMD Radeon RX 6600S and AMD Radeon RX 550X represent two distinct eras of mobile graphics, separated by process node, architecture, and raw compute capability. While both cards occupy the same 49th percentile in the global GPU hierarchy and share a similar average benchmark score profile, the data reveals a decisive performance gulf in head-to-head testing. The RX 6600S is a modern RDNA 2.0 part built for thin-and-light gaming, whereas the RX 550X is a legacy Polaris-era chip aimed at basic acceleration. This analysis breaks down the benchmark results, architectural gaps, and specification differences to clarify where each card stands.

Head-to-Head Benchmarks

The single available direct comparison is a landslide victory for the AMD Radeon RX 6600S. In the Geekbench OpenCL test, the RX 6600S scores 66,435 against the RX 550X’s 9,662. That translates to a 587.6% delta, meaning the RX 6600S delivers nearly seven times the compute throughput in this workload. This is not a marginal generational bump; it is a categorical shift in performance class. For context, the RX 6600S’s average benchmark score across all tests is 10,629, while the RX 550X averages 10,481 — a mere 1.4% difference in aggregate. The discrepancy between the OpenCL blowout and the similar averages highlights how the RX 550X’s other benchmarks (like Geekbench Vulkan) are not included in the shared comparison set, or how the RX 6600S’s other scores drag its average down relative to its OpenCL peak.

The nearest-rival data further contextualizes the RX 6600S’s position. Its average score of 10,629 sits just 0.4% above the AMD Radeon R9 M275X (average 10,582) and 1.4% above the RX 550X (average 10,481). However, it trails the NVIDIA GeForce GTX 560 Ti by 0.6% (average 10,690) and the NVIDIA Quadro K2200 by 1.2% (average 10,761). This suggests that while the RX 6600S dominates the RX 550X in a single compute test, its overall benchmark profile places it in a tight pack with older mid-range cards, not at the top of the heap. The RX 550X, conversely, sees its own rivals: it is 0.8% ahead of the NVIDIA Tesla C2075 (average 10,400), 1.2% ahead of the AMD Radeon RX 6500M (average 10,362), but 1% behind the R9 M275X and 1.4% behind the RX 6600S. The head-to-head delta of 587.6% is the outlier, driven entirely by the OpenCL test where the RX 6600S’s modern architecture and higher shader count shine.

FAQ

Q: Which card has the higher Geekbench OpenCL score?

A: The AMD Radeon RX 6600S scores 66,435 compared to the RX 550X’s 9,662, a 587.6% advantage for the RX 6600S.

Q: Are the two cards comparable in overall average benchmark performance?

A: Yes, their average benchmark scores are close: the RX 6600S averages 10,629 and the RX 550X averages 10,481, a difference of just 1.4%.

Q: What is the process node difference between the two GPUs?

A: The RX 6600S uses a 7 nm process from TSMC, while the RX 550X uses a 14 nm process from GlobalFoundries.

Q: Do both cards support the same DirectX version?

A: No. The RX 6600S supports DirectX 12 Ultimate (12_2), while the RX 550X supports DirectX 12 (12_0).

Q: Which card has more shading units?

A: The RX 6600S has 1,792 shading units, whereas the RX 550X has 512.

Q: Is the RX 550X’s memory bandwidth higher or lower than the RX 6600S?

A: Lower. The RX 550X has 96.00 GB/s bandwidth, while the RX 6600S has 224.0 GB/s.

Architecture Differences

The two GPUs are built on fundamentally different architectures. The RX 6600S uses RDNA 2.0 with the Navi 23 chip, part of the Navi Mobile (RX 6000M) generation. In contrast, the RX 550X uses GCN 4.0 with the Lexa chip, from the Polaris (RX 500X) generation. This architectural split explains most of the performance variance. RDNA 2.0 is designed for higher instruction-level parallelism and lower latency, which directly benefits compute workloads like OpenCL. The RX 6600S’s transistor count is 11,060 million on a 237 mm² die, yielding a density of 46.7M / mm². The RX 550X, by comparison, packs just 2,200 million transistors on a 103 mm² die, with a density of 21.4M / mm². The RX 6600S also integrates 28 ray-tracing cores, a feature entirely absent from the RX 550X (which has null RT cores). Both cards lack tensor cores, but the RX 6600S supports a 2:1 FP16 ratio (14.34 TFLOPS) versus the RX 550X’s 1:1 ratio (1,211.4 GFLOPS), meaning the newer card can double its half-precision throughput, a boon for AI-adjacent or media tasks. The RX 6600S also boasts a higher Vulkan API version (1.4 vs 1.3) and DirectX 12 Ultimate support, enabling hardware-accelerated features like mesh shaders and variable-rate shading, which the RX 550X cannot handle.

Specification Differences

The specification sheet reveals stark contrasts beyond the architecture. The RX 6600S has 1,792 shading units, 112 TMUs, and 64 ROPs, while the RX 550X is limited to 512 shading units, 32 TMUs, and 16 ROPs. This translates to a pixel rate of 128.0 GPixel/s for the RX 6600S versus 18.93 GPixel/s for the RX 550X, and a texture rate of 224.0 GTexel/s versus 37.86 GTexel/s. Clock speeds also differ: the RX 6600S runs at a base of 1700 MHz and boost of 2000 MHz (with a game clock of 1881 MHz), while the RX 550X is slower at 1100 MHz base and 1183 MHz boost. Memory is another divider: the RX 6600S uses 4 GB of GDDR6 at 1750 MHz (14 Gbps effective) on a 128-bit bus, delivering 224.0 GB/s bandwidth. The RX 550X uses 4 GB of GDDR5 at 1500 MHz (6 Gbps effective) on the same 128-bit bus, but only achieves 96.00 GB/s. Power draw differs as well: the RX 6600S has an 80 W TDP and is an integrated form factor (IGP) with no power connectors, while the RX 550X has a 50 W TDP, is dual-slot, and suggests a 250 W PSU. The RX 6600S uses PCIe 4.0 x8, whereas the RX 550X uses PCIe 3.0 x8. Display outputs also diverge: the RX 6600S is “Portable Device Dependent,” while the RX 550X offers 1x DVI, 1x HDMI 2.0b, and 1x DisplayPort 1.4a. The RX 550X is a physical card at 145 mm (5.7 inches) long; the RX 6600S has no listed dimensions. Finally, the RX 6600S was released on 2022-01-03, while the RX 550X predates it by over three years, launching on 2018-12-15.

Where Each One Wins

The AMD Radeon RX 6600S is the clear winner in compute-heavy workloads, as evidenced by its 587.6% lead in Geekbench OpenCL. Its combination of RDNA 2.0 architecture, 1,792 shading units, and 224.0 GB/s bandwidth makes it suited for modern gaming titles that leverage DirectX 12 Ultimate features like ray tracing (via its 28 RT cores) and variable-rate shading. The higher 7 nm process node and 14.34 TFLOPS FP16 performance also give it an edge in content creation or any task that can utilize half-precision math. For mobile users, its 80 W TDP and IGP form factor mean it can be integrated into slim laptops without external power connectors, trading some peak performance for portability.

The AMD Radeon RX 550X, despite its massive defeat in the head-to-head, still has a niche. Its lower 50 W TDP and 250 W suggested PSU make it a more power-efficient choice for legacy systems or basic desktop builds where compute performance is secondary. With 1,211.4 GFLOPS FP32 and a 1:1 FP16 ratio, it is adequate for older DirectX 12 (12_0) titles or as a display output card, offering 1x DVI, 1x HDMI 2.0b, and 1x DisplayPort 1.4a for multi-monitor setups. Its 14 nm process and 103 mm² die size make it cheaper to produce, and its dual-slot form factor with no power connectors allows drop-in upgrades for pre-built PCs with modest power supplies. The RX 550X also has a Vulkan score of 11,299 in Geekbench, a metric the RX 6600S lacks in the data pack, suggesting it may handle Vulkan-based workloads reasonably well relative to its class. In summary, the RX 6600S wins on raw performance and future-proofing, while the RX 550X wins on simplicity, low power draw, and legacy compatibility.