NVIDIA Tesla P100 PCIe 16 GB vs NVIDIA Tesla P40 Comparison

The NVIDIA Tesla P100 PCIe 16 GB and the NVIDIA Tesla P40 are both Pascal-era workstation cards, but the benchmark data reveals they are built for fundamentally different workloads. The single head-to-head benchmark available, Geekbench OpenCL, shows a decisive victory for the P100, though the P40’s specifications and additional Vulkan result paint a more nuanced picture for specific use cases.

Head-to-Head Benchmarks

The only direct comparison available is the Geekbench OpenCL test, and the result is not close. The NVIDIA Tesla P100 PCIe 16 GB scores 79,605 points, while the NVIDIA Tesla P40 manages 62,017 points. This translates to a 28.4% advantage for the P100, a substantial margin that underscores the architectural gulf between the two cards. The P100’s HBM2 memory and dedicated FP16 throughput are the primary drivers of this OpenCL performance, as the test often leverages compute-heavy and memory-bandwidth-intensive operations.

Looking at the broader competitive landscape, the P100’s score places it in the 92nd percentile of all GPUs, with its nearest rivals being the NVIDIA GeForce RTX 5090 (scoring 79,842, a -0.3% delta relative to the P100) and the AMD Radeon Pro Vega 64X (scoring 80,959, a -1.7% delta). This indicates that the P100 is performing at the very top tier of the benchmark database, essentially trading blows with modern flagship consumer and professional cards. The P100 also holds a slim 0.3% lead over its direct sibling, the Tesla P100 PCIe 12 GB, and a 0.8% lead over the AMD Radeon RX 6850M XT.

The P40, by contrast, sits in the 89th percentile, which is still strong but clearly a notch below the P100. Its average benchmark score across all tests is 65,095, which includes its OpenCL result and a Geekbench Vulkan score of 68,172. The Vulkan score is notably higher than its OpenCL score, suggesting the P40’s architecture responds better to the lower-level, driver-optimized API. Its nearest rivals include the AMD Radeon VII (scoring 66,004, a -1.4% delta) and the AMD Radeon Pro WX 9100 (scoring 64,212, a 1.4% delta for the P40). This places the P40 in a competitive mid-to-high tier, but its 28.4% deficit to the P100 in OpenCL is a stark indicator of the P100’s superior raw compute capability.

Where Each One Wins

The P100 is the clear winner in raw computational throughput and memory bandwidth. Its FP32 performance is rated at 9.526 TFLOPS, and crucially, its FP16 performance is 19.05 TFLOPS, achieved at a 2:1 ratio. This means the P100 can process half-precision data at double the rate of single-precision, a feature that is invaluable for AI inference and training workloads that utilize FP16 arithmetic. The P100 also boasts a 4096-bit memory bus connected to 16 GB of HBM2, delivering a staggering 732.2 GB/s of bandwidth. This massive bandwidth is critical for memory-bound tasks like large matrix multiplications and data processing, and it is the primary reason for its dominant OpenCL score.

The P40 wins on capacity and raw pixel/texture throughput. It offers 24 GB of GDDR5 memory on a 384-bit bus, which, while providing a much lower 347.1 GB/s of bandwidth, offers 50% more total memory capacity than the P100. For workloads that require holding large datasets, such as massive inference models or high-resolution rendering scenes that exceed 16 GB, the P40’s larger frame buffer is a decisive advantage. Furthermore, the P40 has higher clock speeds (boost clock of 1531 MHz vs. 1329 MHz) and more shading units (3840 vs. 3584), resulting in higher pixel rate (147.0 GPixel/s vs. 127.6 GPixel/s) and texture rate (367.4 GTexel/s vs. 297.7 GTexel/s). This makes the P40 a stronger candidate for traditional graphics rasterization tasks that are bound by pixel fill and texture filtering, despite the P100’s superior compute performance.

The P40 also has a significant edge in FP16 compute, but in the opposite direction. Its FP16 performance is a minuscule 183.7 GFLOPS, achieved at a 1:64 ratio. This is catastrophically slow for half-precision tasks, confirming that the P40 is not designed for modern AI workloads that rely on FP16. The P100 is the only one of the two that can handle such tasks effectively.

The Verdict

The data is unambiguous: for compute-intensive tasks, particularly those leveraging FP16, the NVIDIA Tesla P100 PCIe 16 GB is the superior choice. Its 28.4% OpenCL lead and its 19.05 TFLOPS FP16 throughput make it the only viable option for AI/ML workloads between the two. Its 732.2 GB/s memory bandwidth also makes it a powerhouse for data-crunching applications.

The NVIDIA Tesla P40 is the better option when memory capacity and traditional graphics throughput are the primary concerns. Its 24 GB memory pool allows it to handle datasets and models that would not fit in the P100’s 16 GB. Its higher pixel and texture rates also make it a more capable choice for rendering tasks that are not compute-limited. However, its abysmal FP16 performance and lower memory bandwidth make it a poor fit for the modern deep learning landscape.

In short, the P100 is for the data scientist and compute specialist; the P40 is for the graphics professional with large memory requirements who does not need FP16 acceleration. The P100 occupies a higher performance percentile (92nd vs. 89th) and its average benchmark score of 79,605 far exceeds the P40’s 65,095 average.

FAQ

Q: Which card has a higher average benchmark score?

A: The NVIDIA Tesla P100 PCIe 16 GB has a significantly higher average benchmark score of 79,605, compared to the NVIDIA Tesla P40’s average of 65,095.

Q: How much faster is the P100 in the OpenCL benchmark?

A: The P100 scores 79,605 points, which is 28.4% higher than the P40’s score of 62,017 points in the Geekbench OpenCL test.

Q: Which card offers more memory capacity?

A: The NVIDIA Tesla P40 offers more memory, with 24 GB of GDDR5, while the P100 has 16 GB of HBM2.

Q: What is the key difference in memory bandwidth?

A: The P100 has a massive bandwidth advantage at 732.2 GB/s, while the P40 offers 347.1 GB/s.

Q: Which card is better suited for FP16 compute workloads?

A: The P100 is the clear winner, with FP16 performance of 19.05 TFLOPS, whereas the P40’s FP16 performance is just 183.7 GFLOPS.

Q: Do either of these cards have display outputs?

A: No, both the NVIDIA Tesla P100 PCIe 16 GB and the NVIDIA Tesla P40 have no display outputs listed in their specifications.

Architecture Differences

The two cards, while sharing the Pascal architecture and a 16 nm TSMC process node, are built on fundamentally different chips. The P100 uses the GP100 chip, a massive 610 mm² die containing 15,300 million transistors. The P40 uses the GP102 chip, which is smaller at 471 mm² and has 11,800 million transistors. Interestingly, both have the same transistor density of 25.1M / mm², reflecting the shared process node.

The memory subsystem is where the architectures diverge most sharply. The P100 is equipped with 16 GB of HBM2 memory on a 4096-bit bus, which is what enables its 732.2 GB/s bandwidth. The P40 uses 24 GB of GDDR5 memory on a 384-bit bus, yielding 347.1 GB/s. This fundamental difference in memory technology dictates their respective strengths: the P100 prioritizes bandwidth, while the P40 prioritizes capacity.

Compute capabilities also differ significantly. The P100 has 3,584 shading units, 224 TMUs, and 96 ROPs, with a pixel rate of 127.6 GPixel/s and a texture rate of 297.7 GTexel/s. The P40 has more of these traditional graphics units, with 3,840 shading units, 240 TMUs, and 96 ROPs, leading to higher pixel and texture rates of 147.0 GPixel/s and 367.4 GTexel/s, respectively. The P100’s base and boost clocks are lower (1190 MHz and 1329 MHz) than the P40’s (1303 MHz and 1531 MHz).

The most critical architectural distinction is FP16 support. The P100 offers FP16 at a 2:1 rate, meaning it executes half-precision operations twice as fast as FP32. The P40’s FP16 is severely gimped at a 1:64 rate, making it effectively useless for that purpose. This single fact makes the P100 a modern compute card and the P40 a legacy graphics-oriented card. Both cards support DirectX 12 (12_1) and OpenGL 4.6, but the P40 offers Vulkan 1.4 support, while the P100 is limited to Vulkan 1.3. Both are dual-slot cards, have a TDP of 250 W, and a suggested PSU of 600 W.