GPU Comparison

The benchmark data clearly separates these two professional NVIDIA GPUs, with the RTX A4000 Mobile holding an overwhelming performance advantage over the Tesla K40m. The sole head-to-head benchmark, Geekbench OpenCL, shows the RTX A4000 Mobile scoring 97,178 points against the Tesla K40m's 19,885 points, a 388.7% difference that defines the entire comparison. However, the Tesla K40m is not without its own arguments, primarily in memory capacity and its historical role as a compute-oriented accelerator.

Where Each One Wins

The RTX A4000 Mobile wins in every measurable performance category available in the data. Its average benchmark score of 21,379 places it in the 66th percentile of all GPUs, while the Tesla K40m's 19,885 average score lands in the 65th percentile, a narrow overall gap that belies the massive single-test disparity. In the Geekbench OpenCL test, the A4000 Mobile's 97,178 score is nearly five times the K40m's 19,885. This indicates the A4000 Mobile is the clear choice for any workload that relies on OpenCL compute acceleration, which encompasses a wide range of scientific, rendering, and data-processing tasks.

The Tesla K40m's advantage is not in speed but in capacity. It offers 12 GB of GDDR5 memory on a 384-bit bus, compared to the A4000 Mobile's 8 GB of GDDR6 on a 256-bit bus. For datasets that exceed 8 GB, the K40m's larger frame buffer could prevent out-of-memory errors, even if processing would be slower. The K40m also has a higher texture unit count (240 TMUs vs 160 TMUs), though this does not translate into a win in any benchmark present in the data. The A4000 Mobile wins on raw throughput, power efficiency, and modern feature support, while the K40m only offers a theoretical capacity advantage for unusually large memory footprints.

Architecture Differences

The two GPUs represent completely different eras of NVIDIA design. The RTX A4000 Mobile is built on the Ampere architecture using the GA104 chip, fabricated on Samsung's 8 nm process. It packs 17,400 million transistors into a 392 mm² die, achieving a transistor density of 44.4 million per square millimeter. In contrast, the Tesla K40m uses the Kepler architecture with the GK110B chip, built on TSMC's 28 nm process. It contains 7,080 million transistors on a larger 561 mm² die, resulting in a density of just 12.6 million per square millimeter. This process advantage alone explains much of the performance gap, as the A4000 Mobile fits more than twice the transistors into a smaller area.

The compute capabilities diverge sharply. The A4000 Mobile features 5,120 shading units, 160 TMUs, and 80 ROPs, along with 40 ray tracing cores and 160 tensor cores. It delivers 17.20 TFLOPS of FP32 performance and matches that with 17.20 TFLOPS of FP16 through a 1:1 ratio. The K40m has 2,880 shading units, 240 TMUs, and only 48 ROPs, with no ray tracing or tensor cores. Its FP32 throughput is 5.046 TFLOPS, and it has no FP16 capability listed in the data. This makes the A4000 Mobile more than three times faster in raw FP32 compute, while also offering dedicated hardware for ray tracing and AI workloads that the K40m simply cannot execute.

Memory systems differ fundamentally as well. The A4000 Mobile uses 8 GB of GDDR6 with 384.0 GB/s of bandwidth, while the K40m uses 12 GB of GDDR5 with 288.4 GB/s. Although the K40m has more memory, the A4000 Mobile's bandwidth is 33% higher, and its effective memory clock of 12 Gbps is double the K40m's 6 Gbps. The A4000 Mobile also supports PCIe 4.0 x16, while the K40m is limited to PCIe 3.0 x16. Power requirements tell a similar story: the A4000 Mobile draws 115 W with no external power connectors, while the K40m consumes 245 W and requires a 550 W power supply. The K40m is a dual-slot card measuring 267 mm, whereas the A4000 Mobile's mobile form factor has no listed dimensions.

Head-to-Head Benchmarks

Only one benchmark test exists in the head-to-head comparison: Geekbench OpenCL. The results are decisive. The RTX A4000 Mobile scores 97,178, while the Tesla K40m scores 19,885. The delta is 388.7%, meaning the A4000 Mobile is nearly four times faster. This is not a marginal win; it is a generational leap. The K40m's score of 19,885 aligns closely with its nearest rivals, the AMD FirePro W7000 scores 19,905 (0.1% higher), and the AMD Radeon RX 6650 XT scores 19,765 (0.6% lower), confirming that the K40m is competitive with its contemporaries but completely outclassed by the modern Ampere part.

The A4000 Mobile's OpenCL score of 97,178 can be contextualized by its nearest rivals. The NVIDIA Quadro RTX 5000 scores 21,629, which is 1.2% higher than the A4000 Mobile's average benchmark score of 21,379, but that comparison is based on the average, not the OpenCL result. The A4000 Mobile's OpenCL score is so far above its average that it suggests the card excels specifically in compute-heavy OpenCL workloads. Meanwhile, the K40m's average score of 19,885 is identical to its OpenCL score, indicating that this single test is representative of its overall performance profile. The A4000 Mobile also shows strength across DirectX tests with Passmark scores of 105 (DX10), 127 (DX11), 66 (DX12), and 157 (DX9), plus a G3D score of 14,796 and a GPU compute score of 6,394. The K40m has no data for these tests, so no comparison is possible, but the A4000 Mobile's Passmark G3D score of 14,796 is substantial.

The Verdict

Choose the NVIDIA RTX A4000 Mobile for virtually any modern workload. The data is unambiguous: it delivers 388.7% higher OpenCL performance than the Tesla K40m, with more than three times the FP32 throughput (17.20 TFLOPS vs 5.046 TFLOPS), higher memory bandwidth (384.0 GB/s vs 288.4 GB/s), and support for ray tracing and tensor cores that the K40m lacks entirely. Its 66th percentile ranking versus the K40m's 65th percentile understates the gap because the percentile is based on average scores, which pull the A4000 Mobile down due to its lower DirectX scores. For compute, rendering, or AI tasks, the A4000 Mobile is the only rational choice from this pair.

The Tesla K40m retains one practical argument: its 12 GB memory capacity exceeds the A4000 Mobile's 8 GB. If a specific workload requires loading models or datasets larger than 8 GB into GPU memory, the K40m could technically handle it, albeit at dramatically reduced speed. The K40m also has a launch MSRP of 7,699 USD, which is a historical fact but not a current purchasing guide. For any new deployment, the A4000 Mobile's combination of speed, efficiency (115 W vs 245 W), and modern API support (DirectX 12 Ultimate vs DirectX 12 11_1, Vulkan 1.4 vs 1.2.175) makes it the superior choice. The K40m is an end-of-life product from 2013, while the A4000 Mobile is end-of-life from 2021, but the eight-year gap in release dates shows in every metric.

FAQ

Q: Which GPU is faster in OpenCL compute?

A: The NVIDIA RTX A4000 Mobile is decisively faster, scoring 97,178 in Geekbench OpenCL versus 19,885 for the Tesla K40m, a 388.7% advantage.

Q: Does the Tesla K40m have any advantage over the RTX A4000 Mobile?

A: Yes, the K40m offers 12 GB of memory compared to 8 GB on the A4000 Mobile, which could be relevant for workloads exceeding 8 GB, though it processes such data much slower.

Q: What are the architecture differences between these two GPUs?

A: The A4000 Mobile uses the Ampere architecture (GA104 chip, 8 nm Samsung process), while the K40m uses Kepler (GK110B chip, 28 nm TSMC process). The A4000 Mobile has 5,120 shading units and 17.20 TFLOPS FP32, versus 2,880 shading units and 5.046 TFLOPS for the K40m.

Q: How do their memory bandwidths compare?

A: The A4000 Mobile provides 384.0 GB/s of bandwidth with 8 GB of GDDR6 on a 256-bit bus, while the K40m provides 288.4 GB/s with 12 GB of GDDR5 on a 384-bit bus.

Q: Which GPU has better API support?

A: The RTX A4000 Mobile supports DirectX 12 Ultimate (12_2) and Vulkan 1.4, while the Tesla K40m supports DirectX 12 (11_1) and Vulkan 1.2.175. Both support OpenGL 4.6.

Q: What is the power consumption difference?

A: The RTX A4000 Mobile has a TDP of 115 W and requires no external power connectors, while the Tesla K40m has a TDP of 245 W and needs a 550 W power supply.

Specification Differences

| Specification | NVIDIA RTX A4000 Mobile | NVIDIA Tesla K40m |

|---|---|---|

| Architecture | Ampere | Kepler |

| Chip | GA104 | GK110B |

| Process Node | 8 nm | 28 nm |

| Transistors | 17,400 million | 7,080 million |

| Die Size | 392 mm² | 561 mm² |

| Transistor Density | 44.4M / mm² | 12.6M / mm² |

| Base Clock | 1140 MHz | 745 MHz |

| Boost Clock | 1680 MHz | 876 MHz |

| Memory Clock | 1500 MHz (12 Gbps effective) | 1502 MHz (6 Gbps effective) |

| Memory Size | 8 GB | 12 GB |

| Memory Type | GDDR6 | GDDR5 |

| Memory Bus Width | 256 bit | 384 bit |

| Memory Bandwidth | 384.0 GB/s | 288.4 GB/s |

| Shading Units | 5120 | 2880 |

| TMUs | 160 | 240 |

| ROPs | 80 | 48 |

| RT Cores | 40 | None |

| Tensor Cores | 160 | None |

| Pixel Rate | 134.4 GPixel/s | 52.56 GPixel/s |

| Texture Rate | 268.8 GTexel/s | 210.2 GTexel/s |

| FP32 Performance | 17.20 TFLOPS | 5.046 TFLOPS |

| FP16 Performance | 17.20 TFLOPS (1:1) | None |

| TDP | 115 W | 245 W |

| Slot Width | None (mobile) | Dual-slot |

| Power Connectors | None | None listed |

| Suggested PSU | None | 550 W |

| Bus Interface | PCIe 4.0 x16 | PCIe 3.0 x16 |

| Display Outputs | Portable Device Dependent | No outputs |

| DirectX | 12 Ultimate (12_2) | 12 (11_1) |

| Vulkan | 1.4 | 1.2.175 |

| Length | None | 267 mm (10.5 inches) |

| Release Date | 2021-04-11 | 2013-11-21 |

| Predecessor | Quadro Turing-M | Tesla Fermi |

| Successor | Ada-MW | Tesla Maxwell |

| Launch MSRP | None | 7,699 USD |