AMD Radeon RX 6650M vs NVIDIA GeForce RTX 4090 Comparison

The AMD Radeon RX 6650M and NVIDIA GeForce RTX 4090 occupy opposite ends of the GPU spectrum, and the benchmark data confirms a decisive performance gulf between them. The RTX 4090 wins both head-to-head tests, but the RX 6650M still holds its own as a capable mobile part with a distinct feature set. This analysis breaks down where each card excels, the architectural differences that explain the gap, and what the numbers mean for real-world selection.

Where Each One Wins

The data is unambiguous: the NVIDIA GeForce RTX 4090 wins every single head-to-head benchmark recorded. In Geekbench OpenCL, the RTX 4090 scores 255,416 against the RX 6650M’s 65,800, a delta of -74.2% from the AMD card’s perspective. The Geekbench Vulkan test tells a similar story, with the RTX 4090 posting 271,631 versus 77,735, a -71.4% difference. There are zero benchmark wins for the AMD Radeon RX 6650M in this comparison.

However, winning tests is not the same as being the right choice for every scenario. The RX 6650M is designed for mobile platforms, as indicated by its "IGP" slot width and "Portable Device Dependent" display outputs. Its 120 W TDP and lack of power connectors make it suitable for thin-and-light laptops where power draw is a primary constraint. The RTX 4090, by contrast, is a triple-slot desktop behemoth requiring a 450 W TDP, a 1x 16-pin power connector, and a suggested 850 W power supply. Its physical dimensions of 304 mm in length, 137 mm in height, and 61 mm in width further cement its role as a desktop-only part.

The RTX 4090 also wins on raw specifications that translate to compute workloads. Its 82.58 TFLOPS FP32 throughput is nearly ten times the RX 6650M’s 8.659 TFLOPS. Memory bandwidth is similarly lopsided: 1.01 TB/s versus 224.0 GB/s. For users running heavy compute, ray tracing, or high-resolution gaming, the RTX 4090 is the clear victor. The RX 6650M, meanwhile, wins on portability and efficiency—it can operate without external power, a feat the RTX 4090 cannot match.

Architecture Differences

The two GPUs come from fundamentally different design philosophies. The AMD Radeon RX 6650M uses the Navi 23 chip built on RDNA 2.0 architecture, manufactured on TSMC’s 7 nm process. It packs 11,060 million transistors into a 237 mm² die, yielding a transistor density of 46.7 million per mm². The NVIDIA GeForce RTX 4090 uses the AD102 chip based on Ada Lovelace architecture, fabricated on TSMC’s 5 nm node. This newer process allows for 76,300 million transistors across a 609 mm² die, achieving a density of 125.3 million per mm²—nearly three times the AMD part.

Core configurations diverge sharply. The RX 6650M has 1,792 shading units, 112 texture mapping units (TMUs), 64 raster operation units (ROPs), and 28 ray tracing cores. It has no dedicated tensor cores. The RTX 4090 scales this up dramatically with 16,384 shading units, 512 TMUs, 176 ROPs, 128 ray tracing cores, and 512 tensor cores. The shading unit count alone is over nine times higher on the NVIDIA card.

Clock speeds tell a subtler story. The RX 6650M has a base clock of 2068 MHz, a boost of 2416 MHz, and a game clock of 2222 MHz. The RTX 4090’s base clock of 2235 MHz and boost of 2520 MHz are higher, but the gap is far narrower than in core counts. Memory configurations also differ: the RX 6650M uses 8 GB of GDDR6 on a 128-bit bus, while the RTX 4090 has 24 GB of GDDR6X on a 384-bit bus. The effective memory speeds are 14 Gbps and 21 Gbps, respectively.

Both architectures support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, so API compatibility is identical. The RTX 4090 adds tensor cores, which the RX 6650M lacks entirely—a key difference for AI and machine learning workloads. The RX 6650M offers FP16 at 17.32 TFLOPS (2:1 ratio), while the RTX 4090 delivers 82.58 TFLOPS FP16 (1:1 ratio), meaning the NVIDIA card does not sacrifice FP32 throughput to achieve FP16 rates.

The Verdict

The benchmark data points to a simple conclusion: the NVIDIA GeForce RTX 4090 is in a different performance class entirely. Its Geekbench OpenCL score of 255,416 is roughly 3.9 times the RX 6650M’s 65,800. The Vulkan result is even more lopsided at 271,631 versus 77,735, a 3.5 times advantage. For any workload where raw GPU compute is the bottleneck, the RTX 4090 is the only rational choice from these two.

But the RX 6650M has its own domain. Its 120 W TDP and IGP form factor make it viable for portable systems where the RTX 4090’s 450 W TDP and triple-slot design are physically impossible. The RX 6650M also carries a 91st percentile ranking against all GPUs, which is respectable for a mobile part. The RTX 4090, despite its dominance, sits at an 88th percentile—a quirk of the averaging methodology, since its average benchmark score of 60,347 is dragged down by low Passmark sub-scores (e.g., 150 in DirectX 12, 224 in DirectX 10) that likely reflect driver or test anomalies rather than real-world capability.

Who should pick which? Users building a desktop workstation or high-end gaming rig with a 850 W power supply and space for a 304 mm card should choose the RTX 4090 without hesitation. Its 24 GB of GDDR6X memory and 512 tensor cores make it suitable for large datasets and AI inference. Users needing a mobile GPU for a laptop, where power draw and physical size are paramount, should select the RX 6650M. It offers competitive performance for its class, as evidenced by its proximity to the NVIDIA TITAN X Pascal (0.5% behind) in the rivals list, while requiring no external power connectors.

FAQ

Q: How much faster is the RTX 4090 than the RX 6650M in OpenCL?

A: The RTX 4090 scores 255,416 in Geekbench OpenCL, which is 74.2% higher than the RX 6650M’s 65,800. This represents roughly a 3.9x performance advantage.

Q: Does the RX 6650M have any advantage in the head-to-head tests?

A: No. The RX 6650M loses both recorded benchmarks—Geekbench OpenCL and Geekbench Vulkan—with deltas of -74.2% and -71.4%, respectively. It records zero wins in the head-to-head comparison.

Q: What is the memory configuration difference between these two GPUs?

A: The RX 6650M has 8 GB of GDDR6 on a 128-bit bus with 224.0 GB/s bandwidth. The RTX 4090 has 24 GB of GDDR6X on a 384-bit bus with 1.01 TB/s bandwidth.

Q: Which GPU has more ray tracing cores?

A: The RTX 4090 has 128 ray tracing cores, compared to 28 on the RX 6650M. The NVIDIA card also has 512 tensor cores, which the AMD part lacks entirely.

Q: Can the RX 6650M be used in a desktop PC?

A: The data suggests it is not designed for that. Its slot width is listed as "IGP" and its power connectors as "None," indicating it is intended for integrated mobile platforms where power is supplied through the motherboard.

Q: How do these GPUs compare in FP32 compute throughput?

A: The RTX 4090 delivers 82.58 TFLOPS of FP32 performance, which is roughly 9.5 times the RX 6650M’s 8.659 TFLOPS.

Head-to-Head Benchmarks

The two recorded head-to-head tests paint a consistent picture of NVIDIA dominance, but the magnitudes deserve closer inspection. In Geekbench OpenCL, the RTX 4090’s 255,416 score dwarfs the RX 6650M’s 65,800. The percentage delta of -74.2% means the AMD card achieves less than a quarter of the NVIDIA card’s throughput. This test exercises general-purpose compute on the GPU, and the results align with the raw specification gap: 16,384 shading units and 82.58 TFLOPS versus 1,792 shading units and 8.659 TFLOPS.

The Geekbench Vulkan test shows a slightly smaller but still massive gap. The RTX 4090 scores 271,631, while the RX 6650M manages 77,735, a -71.4% delta. Interestingly, the Vulkan scores for both cards are higher than their OpenCL scores—a 6.3% improvement for the RTX 4090 and an 18.1% improvement for the RX 6650M. This suggests the AMD architecture scales better with Vulkan’s lower-level API, though it remains far behind in absolute terms.

Context from the nearest rivals list adds nuance. The RX 6650M’s average benchmark score of 71,768 places it just 0.5% behind the NVIDIA TITAN X Pascal (72,098) and 0.8% behind the AMD Radeon Pro Vega 64 (72,379). It is 1.3% ahead of the AMD Radeon RX 6600 LE (70,829). These are older or lower-tier desktop cards, yet the mobile RX 6650M trades blows with them—evidence of its efficiency. The RTX 4090’s average score of 60,347 is puzzlingly lower than its individual Geekbench scores, due to the Passmark results (e.g., 150 in DirectX 12, 326 in DirectX 11) that skew the average downward. Its nearest rival, the Intel Arc Pro A60, matches it at 60,326 with a 0% delta, which is an artifact of the averaging methodology rather than a reflection of real-world parity.

In practical terms, the RTX 4090’s wins are so decisive that no workload in the available data favors the RX 6650M. The only question is whether the AMD part’s portability and low power draw matter more than raw performance—and the data suggests they do, but only for a very specific mobile use case.