AMD Radeon RX 6650 XT vs NVIDIA Tesla K40m Comparison

Head-to-Head Benchmarks

The only directly comparable benchmark in the database is Geekbench OpenCL, and the result is decisively one-sided. The NVIDIA Tesla K40m scores 19,885, while the AMD Radeon RX 6650 XT manages just 10,111. That is a 96.7% advantage for the Tesla K40m — nearly double the AMD card’s compute output in this specific OpenCL workload. This is a striking outcome given the generational gap between the two products, and it underscores how differently these GPUs are optimized for compute-oriented tasks.

However, the aggregate benchmark picture is far closer. The Tesla K40m holds an average benchmark score of 19,885, while the RX 6650 XT sits at 19,765. The difference is a mere 0.6% in favor of the NVIDIA card. In the nearest-rival context, the Tesla K40m is 0.1% behind the AMD FirePro W7000 (19,905), 1.3% ahead of the AMD FirePro D300 (19,637), and 1.4% ahead of the NVIDIA Quadro K5200 (19,602). The RX 6650 XT, meanwhile, is 0.7% ahead of the FirePro D300, 0.8% ahead of the Quadro K5200, and 0.7% behind the FirePro W7000. Both cards occupy the same performance tier in the aggregate, landing at the 65th percentile of all GPUs in the database.

The RX 6650 XT’s benchmark suite is far more extensive, covering DirectX 9 through 12, Vulkan, Metal, and compute workloads. Its strongest showing is in Geekbench Metal, where it scores 97,969, followed by Geekbench Vulkan at 81,306. Passmark G3D yields 17,166, and Passmark GPU Compute reaches 7,532. The DirectX tests are lower: Passmark DirectX 12 scores 62, DirectX 11 scores 169, DirectX 10 scores 109, and DirectX 9 scores 215. The 2D test is 918. These numbers are not directly comparable to the Tesla K40m, which only has the single OpenCL result, but they illustrate the breadth of the AMD card’s capability across modern APIs.

Architecture Differences

The architectural divide here is vast. The Tesla K40m is built on NVIDIA’s Kepler architecture, using the GK110B chip on a 28 nm process from TSMC. The RX 6650 XT employs AMD’s RDNA 2.0 architecture, with the Navi 23 chip on TSMC’s 7 nm node. The process shrink is dramatic: 28 nm versus 7 nm translates into a transistor density of 12.6 million transistors per square millimeter for the Tesla versus 46.7 million for the RX 6650 XT. The Tesla packs 7,080 million transistors across a 561 mm² die, while the RX 6650 XT fits 11,060 million transistors into just 237 mm².

The memory subsystems are similarly divergent. The Tesla K40m carries 12 GB of GDDR5 on a 384-bit bus, delivering 288.4 GB/s of bandwidth. The RX 6650 XT has 8 GB of GDDR6 on a 128-bit bus, with 280.3 GB/s of bandwidth. Despite the narrower bus, the newer GDDR6 memory at 17.5 Gbps effective nearly matches the older GDDR5 at 6 Gbps effective. Clock speeds tell the rest of the story: the Tesla runs at a 745 MHz base and 876 MHz boost, while the RX 6650 XT operates at 2,055 MHz base, 2,410 MHz game, and 2,635 MHz boost.

Compute resources are organized differently. The Tesla has 2,880 shading units, 240 TMUs, and 48 ROPs, with pixel rate of 52.56 GPixel/s and texture rate of 210.2 GTexel/s. Its FP32 throughput is 5.046 TFLOPS. The RX 6650 XT has 2,048 shading units, 128 TMUs, and 64 ROPs, yet achieves higher rates: 168.6 GPixel/s and 337.3 GTexel/s, with FP32 at 10.79 TFLOPS. The AMD card also includes 32 ray tracing cores and supports FP16 at 21.59 TFLOPS (2:1), features entirely absent from the Tesla. The RX 6650 XT draws 176 W versus the Tesla’s 245 W, and requires a 450 W PSU versus 550 W.

API support differs meaningfully. The Tesla supports DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.175. The RX 6650 XT supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The bus interface also differs: PCIe 3.0 x16 for the Tesla, PCIe 4.0 x8 for the RX 6650 XT. The Tesla has no display outputs, while the RX 6650 XT offers 1x HDMI 2.1 and 3x DisplayPort 1.4a.

Where Each One Wins

The Tesla K40m wins in raw OpenCL compute performance, and it wins by a massive margin. Its 19,885 Geekbench OpenCL score against the RX 6650 XT’s 10,111 shows that the older card is still formidable in compute-heavy workloads that leverage OpenCL specifically. This is consistent with its heritage as a Tesla-branded compute accelerator, designed for scientific and professional computing rather than graphics output. The 12 GB memory capacity is also advantageous for large datasets, even if the bandwidth is only marginally better than the RX 6650 XT’s.

The RX 6650 XT wins in nearly every other measurable category. It has modern API support, including DirectX 12 Ultimate and Vulkan 1.4, which the Tesla cannot match. Its FP32 throughput is more than double (10.79 TFLOPS versus 5.046 TFLOPS), and it adds ray tracing cores and FP16 support. The clock speeds are roughly three times higher, and the pixel and texture rates are substantially better. The power efficiency is superior: 176 W versus 245 W for the same performance class. The RX 6650 XT also has display outputs, making it a functional graphics card, whereas the Tesla is compute-only.

In the aggregate benchmark score, the two cards are statistically tied. The 0.6% delta between them is negligible in real-world terms. But the workload profile matters: the Tesla’s single benchmark result is an OpenCL compute test, while the RX 6650 XT’s average is pulled across a broad suite including gaming-oriented DirectX tests, Vulkan, and Metal. The RX 6650 XT’s Passmark G3D score of 17,166 and GPU Compute of 7,532 indicate strong general-purpose and graphics performance, while its DirectX 12 score of 62 suggests that modern gaming workloads are within its reach. The Tesla has no comparable gaming benchmarks, reflecting its intended role.

FAQ

Q: Which GPU has the higher aggregate benchmark score?

A: The NVIDIA Tesla K40m averages 19,885, while the AMD Radeon RX 6650 XT averages 19,765. The difference is 0.6% in favor of the Tesla K40m.

Q: How much faster is the Tesla K40m in Geekbench OpenCL?

A: The Tesla K40m scores 19,885 versus the RX 6650 XT’s 10,111, a 96.7% advantage for the NVIDIA card.

Q: Does the RX 6650 XT support ray tracing?

A: Yes, it includes 32 ray tracing cores. The Tesla K40m has no ray tracing cores listed.

Q: What is the memory configuration difference?

A: The Tesla K40m has 12 GB of GDDR5 on a 384-bit bus with 288.4 GB/s bandwidth. The RX 6650 XT has 8 GB of GDDR6 on a 128-bit bus with 280.3 GB/s bandwidth.

Q: Which card has better API support?

A: The RX 6650 XT supports DirectX 12 Ultimate (12_2) and Vulkan 1.4. The Tesla K40m supports DirectX 12 (11_1) and Vulkan 1.2.175. Both support OpenGL 4.6.

Q: What is the power draw difference?

A: The Tesla K40m has a TDP of 245 W with a suggested 550 W PSU. The RX 6650 XT has a TDP of 176 W with a suggested 450 W PSU.

The Verdict

The data presents a clear split based on workload. For OpenCL compute tasks, the NVIDIA Tesla K40m is the unambiguous choice. Its 96.7% lead in Geekbench OpenCL is not a marginal advantage; it is a dominant one. The 12 GB memory capacity and Kepler’s compute orientation make this card a viable option for scientific or professional compute environments that rely on OpenCL. The aggregate score being essentially tied (0.6% difference) reinforces that the Tesla is not obsolete in compute terms, despite its 2013 release.

For everything else, the AMD Radeon RX 6650 XT is the superior product. It delivers more than double the FP32 throughput, adds ray tracing and FP16 support, and offers modern API coverage including DirectX 12 Ultimate and Vulkan 1.4. It is more power-efficient, has display outputs, and supports PCIe 4.0. Its benchmark suite shows strong results across Metal, Vulkan, and DirectX, making it a versatile card for gaming, general graphics, and mixed workloads. The 8 GB GDDR6 memory is smaller but compensated by higher effective clock speeds.

The production status of both cards is end-of-life, so neither is a forward-looking purchase. The launch MSRP of the Tesla K40m was 7,699 USD, while the RX 6650 XT launched at 399 USD. The performance parity in aggregate scores despite the massive price difference highlights how much the market has changed. The choice comes down to specific needs: OpenCL compute with large memory demands points to the Tesla K40m; modern graphics, gaming, and balanced compute point squarely to the RX 6650 XT. The data does not support a single winner — it supports two winners for two very different jobs.