NVIDIA Tesla K40c

NVIDIA Tesla K40c is a compute-centric accelerator whose benchmark results place it in a narrow performance band, sitting just below a cluster of AMD workstation and consumer cards. Its Geekbench OpenCL score of 17,468 places it at the 59th percentile among all GPUs, indicating a mid-pack standing in the broader graphics landscape. The data shows a card that trades at the edge of its performance class, with the nearest rivals all within a 1.8% margin, making the K40c a marginal underperformer in raw compute benchmarks while offering a distinct feature set for professional workloads.

Benchmark Performance

The Tesla K40c delivers a Geekbench OpenCL score of 17,468, which positions it at the 59th percentile of all GPUs. This percentile rank clarifies that while the card is not a top-tier performer in synthetic compute tests, it still outpaces a majority of the GPU landscape. The benchmark results indicate a tightly contested performance tier: the AMD Radeon Pro 560 leads the K40c by a negligible 0.2%, scoring 17,497. This margin is effectively a statistical tie, suggesting the two cards deliver near-identical compute throughput in this workload.

Moving down the rival list, the AMD Radeon Pro 460 scores 17,575, which is 0.6% ahead of the K40c. The AMD Radeon HD 7790 achieves 17,666, a 1.1% advantage, and the AMD FirePro W7000 posts 17,790, leading by 1.8%. These deltas are compact, with the entire spread from the K40c to the fastest rival spanning under two percentage points. In practical terms, the K40c is effectively performance-equivalent to these cards in OpenCL compute, with differences that fall well within typical run-to-run variance. The 5.046 TFLOPS of FP32 throughput and 210.2 GTexel/s texture rate are the architectural underpinnings of this score, though the benchmark result itself shows the card does not convert its raw specifications into a decisive lead over the AMD competitors.

Power and Cooling

The Tesla K40c carries a thermal design power (TDP) of 245 W, which dictates its cooling and power delivery requirements. The card is a dual-slot design, indicating it will occupy two expansion slots in a chassis, and it requires both a 6-pin and an 8-pin power connector for operation. The suggested power supply unit (PSU) rating is 550 W, which provides a baseline for system builders to ensure stable operation under load. The 245 W TDP is a moderate figure for a compute accelerator of this era, and the dual-slot cooler is designed to dissipate that heat within a server or workstation chassis. The data shows no alternative power configurations, so the 6-pin plus 8-pin requirement is mandatory. The combination of a 550 W PSU recommendation and dual connectors indicates the card expects a robust power delivery system, though the exact thermal solution is not detailed beyond its slot width.

Memory Subsystem

Memory capacity is a defining strength of the Tesla K40c, featuring 12 GB of GDDR5 VRAM on a 384-bit bus. This configuration yields a memory bandwidth of 288.4 GB/s, a figure that supports high-resolution workloads but is not exceptional by modern standards. The 12 GB capacity is substantial, allowing large datasets and textures to reside on-card, which is critical for scientific computing and rendering tasks that exceed the VRAM limits of consumer GPUs. The 384-bit bus width provides a wide path for data transfer, though the effective memory clock of 6 Gbps keeps bandwidth at 288.4 GB/s. For high-resolution rendering, the ample VRAM capacity is more significant than raw bandwidth; the card can hold full scenes or large volumetric data without spilling to system memory. However, the bandwidth figure suggests that memory-heavy operations may experience bottlenecks when moving data across the bus, particularly in real-time workloads. The 52.56 GPixel/s pixel rate and 48 ROPs further indicate that the card is not optimized for high fill-rate scenarios, but rather for compute tasks where memory capacity and FP32 throughput take precedence.

How It Compares

AMD Radeon Pro 560: This is the closest rival, with an average score of 17,497, a mere 0.2% ahead of the K40c. Benchmark results indicate the two are functionally identical in OpenCL compute performance. The K40c offers far more VRAM (12 GB versus the Pro 560’s unspecified capacity), giving it an edge in memory-bound workloads, but the Pro 560 achieves parity in raw compute speed.

AMD Radeon Pro 460: The Pro 460 scores 17,575, which is 0.6% higher than the K40c. This delta is small enough to be considered negligible in real-world applications. The K40c’s advantage lies in its compute-oriented design and larger memory footprint, while the Pro 460 edges ahead in this synthetic benchmark, suggesting slightly better optimization in OpenCL execution.

AMD Radeon HD 7790: With a score of 17,666, the HD 7790 leads the K40c by 1.1%. This consumer card outperforms the Tesla in this specific test, highlighting that the K40c’s value is not in peak compute scores but in its professional feature set and memory capacity. The HD 7790 is a lower-tier product, yet it matches or beats the K40c in raw throughput, underscoring the age of the Tesla architecture.

AMD FirePro W7000: The FirePro W7000 posts the highest score among rivals at 17,790, a 1.8% lead over the K40c. This is the largest delta in the group, but still a narrow margin. The W7000 is a workstation card like the K40c, and the data shows it holds a slight performance edge in OpenCL. The K40c counters with more VRAM and a higher transistor count (7,080 million versus unspecified), but the benchmark verdict favors the FirePro in this metric.

Who Should Consider It

Benchmark results indicate the Tesla K40c is suited for users who prioritize memory capacity over peak compute speed. The 12 GB VRAM is the standout feature, making the card viable for workloads that require large datasets, such as deep learning inference, scientific simulations, or high-resolution texture rendering. At 1080p or 1440p gaming, the card’s 5.046 TFLOPS of FP32 performance is sufficient for many titles at medium settings, but the 59th percentile ranking suggests it is not a high-end gaming solution. For compute tasks that are VRAM-bound, the K40c excels; the 288.4 GB/s bandwidth and 384-bit bus handle large memory allocations efficiently. However, for users seeking maximum OpenCL performance, the rivals listed all offer slightly higher scores, making them technically faster in synthetic tests. The K40c is best considered for professional environments where the 12 GB frame buffer is non-negotiable, and where the lack of display outputs (the card has no outputs) is acceptable since it is designed for headless compute servers. Gamers or workstation users requiring a display output must look elsewhere, as this card is purely an accelerator.

FAQ

Q: How does the Tesla K40c compare to the AMD Radeon Pro 560 in compute performance?

A: The Radeon Pro 560 has an average score of 17,497, which is 0.2% higher than the K40c’s 17,468. The performance difference is negligible, effectively a tie in OpenCL benchmarks.

Q: What is the memory bandwidth of the K40c and why does it matter?

A: The K40c has a memory bandwidth of 288.4 GB/s, delivered via a 384-bit bus with GDDR5 memory. This bandwidth supports moving large data sets, but it is not exceptionally high, so memory-heavy tasks may be limited by transfer speed rather than capacity.

Q: Can the Tesla K40c be used for gaming with a monitor connected?

A: No. The card has no display outputs, meaning it cannot connect to a monitor. It is designed exclusively for compute workloads in a server or workstation environment.

Q: What power supply is recommended for the K40c?

A: The suggested PSU rating is 550 W, and the card requires both a 6-pin and an 8-pin power connector. Ensure your power supply has these connectors available.

Q: What is the FP32 performance of the K40c?

A: The card delivers 5.046 TFLOPS of FP32 compute throughput, which is a measure of its single-precision floating-point performance for general compute tasks.

Q: Does the K40c support modern graphics APIs?

A: Yes, it supports DirectX 12 (11_0), OpenGL 4.6, and Vulkan 1.2.175. However, the DirectX support is limited to the 11_0 feature level, which may restrict some newer effects.

Ray Tracing and Feature Set

The Tesla K40c is based on the Kepler architecture and the GK180 chip, built on a 28 nm process at TSMC. It contains 7,080 million transistors on a 561 mm² die, with a transistor density of 12.6 million per square millimeter. The card does not have dedicated ray tracing cores or tensor cores, as these features were introduced in later architectures. Consequently, any ray tracing workloads must be handled through compute shaders or OpenCL, which is inefficient compared to hardware-accelerated solutions. The API support includes Vulkan 1.2.175 and OpenGL 4.6, which allow for modern graphics programming, but DirectX 12 support is limited to the 11_0 feature level, meaning it cannot leverage full DirectX 12 Ultimate features like mesh shaders or variable rate shading. The lack of tensor cores also means no hardware acceleration for AI inference tasks that rely on these units, though the 2880 shading units can perform general-purpose compute. The card’s feature set is thus oriented toward raw FP32 compute and memory capacity, with no modern hardware acceleration for ray tracing or machine learning. The pixel rate of 52.56 GPixel/s and texture rate of 210.2 GTexel/s are modest, reinforcing that this is not a graphics-first product but a compute accelerator with a legacy architecture.