AMD Radeon RX 6650M XT vs NVIDIA GeForce RTX 4090 D Comparison

FAQ

Q: How does the NVIDIA GeForce RTX 4090 D compare to the AMD Radeon RX 6650M XT in the database's sole head-to-head benchmark?

A: In the Geekbench OpenCL test, the RTX 4090 D scores 278,621 against 76,904 for the RX 6650M XT, a delta of 262.3% in favor of the NVIDIA part.

Q: Which GPU holds a higher percentile ranking among all GPUs in the database?

A: The RTX 4090 D sits at the 98th percentile, while the RX 6650M XT is at the 91st percentile.

Q: What are the memory configurations of the two cards?

A: The RTX 4090 D has 24 GB of GDDR6X on a 384-bit bus with 1.01 TB/s bandwidth. The RX 6650M XT has 8 GB of GDDR6 on a 128-bit bus with 256.0 GB/s bandwidth.

Q: Which architecture does each GPU use, and on what process node?

A: The RTX 4090 D uses Ada Lovelace on TSMC's 5 nm node. The RX 6650M XT uses RDNA 2.0 on TSMC's 7 nm node.

Q: What is the power draw difference between the two?

A: The RTX 4090 D is rated at 425 W TDP, whereas the RX 6650M XT is rated at 120 W TDP.

Q: Are both cards still in production?

A: No, both are listed as end-of-life in the database.

Where Each One Wins

The data splits cleanly along performance and form factor lines. The RTX 4090 D wins the only recorded shared benchmark, the Geekbench OpenCL test, by a massive 262.3% margin. That result aligns with its 98th percentile ranking and an average benchmark score of 178,050. The RX 6650M XT, meanwhile, carries a 91st percentile ranking and an average score of 76,904, still strong, but in a different performance class.

The RX 6650M XT wins on efficiency and physical footprint. Its TDP is 120 W versus 425 W, and it is an IGP (integrated graphics processor) with no power connectors required. The RTX 4090 D is a triple-slot card requiring a 1x 16-pin connector and an 800 W suggested PSU. The AMD part's portable device dependent display outputs contrast sharply with the NVIDIA card's fixed 1x HDMI 2.1 and 3x DisplayPort 1.4a outputs.

For compute, the RTX 4090 D dominates: 73.54 TFLOPS FP32 versus 9.896 TFLOPS for the AMD card. The NVIDIA part also has a higher pixel rate (443.5 GPixel/s versus 154.6 GPixel/s) and texture rate (1,149.1 GTexel/s versus 309.2 GTexel/s). The RX 6650M XT only wins in FP16 throughput relative to its own FP32, offering 19.79 TFLOPS at a 2:1 ratio, but that figure is still far below the RTX 4090 D's 73.54 TFLOPS FP16.

Architecture Differences

The RTX 4090 D is built on Ada Lovelace, NVIDIA's architecture from the GeForce 40 generation. It uses the AD102 chip manufactured by TSMC on a 5 nm process. The die is enormous: 609 mm² with 76,300 million transistors, yielding a transistor density of 125.3M per mm². The chip includes 14,592 shading units, 456 TMUs, 176 ROPs, 114 RT cores, and 456 tensor cores. Tensor cores are a notable feature here, as the AMD part has none listed.

The RX 6650M XT belongs to AMD's RDNA 2.0 architecture, part of the Radeon RX 6000 series and the Navi Mobile generation. It uses the Navi 23 chip on TSMC's 7 nm process. The die is 237 mm² with 11,060 million transistors, a density of 46.7M per mm². It has 2,048 shading units, 128 TMUs, 64 ROPs, and 32 RT cores. The absence of tensor cores reflects a fundamentally different compute design philosophy: NVIDIA dedicates silicon to AI acceleration, while AMD focuses on a leaner shader-based layout.

Both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The transistor density gap is striking: the RTX 4090 D packs nearly 2.7 times more transistors per square millimeter. That density difference, combined with the 5 nm versus 7 nm process gap, explains why the NVIDIA chip can field more than seven times the shading units and nearly four times the ROPs.

Specification Differences

The clock behavior differs significantly. The RTX 4090 D runs a 2280 MHz base and 2520 MHz boost, with memory at 1313 MHz (21 Gbps effective). The RX 6650M XT has a 2068 MHz base, 2416 MHz boost, and a 2162 MHz game clock, with memory at 2000 MHz (16 Gbps effective). The AMD card's higher game clock is notable, but architectural throughput differences overwhelm it.

Memory is the widest gap. The RTX 4090 D ships with 24 GB of GDDR6X across a 384-bit bus, delivering 1.01 TB/s. The RX 6650M XT has 8 GB of GDDR6 across a 128-bit bus, delivering 256.0 GB/s. That is a 4x difference in bus width and bandwidth.

The form factors are entirely different categories. The RTX 4090 D is a triple-slot card measuring 304 mm in length, 137 mm in height, and 61 mm in width, requiring a 16-pin power connector and an 800 W suggested PSU. The RX 6650M XT is an IGP with no power connectors and no listed dimensions, designed for portable devices. The bus interface also differs: PCIe 4.0 x16 for NVIDIA versus PCIe 4.0 x8 for AMD.

The RTX 4090 D has a launch MSRP of 1,599 USD, while the RX 6650M XT has no launch MSRP recorded. The NVIDIA card's predecessor is the GeForce 30 series and its successor is the GeForce 50 series. The AMD card's predecessor is Polaris Mobile and it has no successor listed.

Head-to-Head Benchmarks

The database records one head-to-head benchmark between these two: Geekbench OpenCL. The RTX 4090 D scores 278,621, while the RX 6650M XT scores 76,904. The delta is 262.3% in favor of NVIDIA. This is not a close contest; it is a full performance tier separation.

Looking at the nearest rivals in the database puts the gap in context. The RTX 4090 D's closest competitors are the NVIDIA RTX PRO 5000 Blackwell (average score 182,109, delta -2.2%), the NVIDIA A100 SXM4 80 GB (183,725, -3.1%), the NVIDIA RTX 5000 Ada Generation (184,664, -3.6%), and the NVIDIA A100 SXM4 40 GB (187,147, -4.9%). The 4090 D trails the fastest of those by only 4.9%, meaning it sits in elite company.

The RX 6650M XT's nearest rivals are far closer in score. The NVIDIA GeForce RTX 5090 D averages 77,712, a 1% delta. The AMD Radeon RX 6850M XT averages 78,940, a 2.6% delta. The NVIDIA Tesla P100 PCIe 12 GB averages 79,396, a 3.1% delta, and the Tesla P100 PCIe 16 GB averages 79,605, a 3.4% delta. The RX 6650M XT is competitive within its own class, just a few percentage points behind the leaders.

The pattern is clear: the RTX 4090 D competes with workstation and data center class parts, while the RX 6650M XT trades blows with mobile and older server GPUs. The 262.3% OpenCL gap between the two reviewed cards is consistent with their average benchmark scores, which differ by roughly 101,146 points.

The Verdict

The data paints an unambiguous picture for raw performance: the NVIDIA GeForce RTX 4090 D is in a different league. Its Geekbench OpenCL score of 278,621 is 262.3% higher than the RX 6650M XT's 76,904. Its 73.54 TFLOPS FP32, 1.01 TB/s memory bandwidth, and 24 GB of VRAM make it a compute powerhouse. The 98th percentile ranking and average score of 178,050 confirm it belongs with professional-grade parts like the RTX PRO 5000 Blackwell and A100 series.

The AMD Radeon RX 6650M XT is not without merit. Its 120 W TDP, IGP form factor, and lack of power connectors make it suitable for portable devices where the triple-slot, 425 W RTX 4090 D physically cannot fit. Its 91st percentile ranking and average score of 76,904 place it near the RTX 5090 D and RX 6850M XT, respectable company for a mobile part. The 2:1 FP16 ratio (19.79 TFLOPS versus 9.896 TFLOPS FP32) is a clever design choice for mixed-precision workloads.

For a desktop workstation or high-end gaming rig, the RTX 4090 D is the clear choice based on every performance metric in the database. For a thin-and-light laptop or any power-constrained environment, the RX 6650M XT is the only viable option of the two. The decision is not about which is better in absolute terms; it is about which class of device you need. The data shows two products designed for entirely different physical and thermal envelopes, with performance scaling accordingly.