NVIDIA T400 4 GB vs NVIDIA Tesla K80 Comparison

Head-to-Head Benchmarks

The recorded benchmark data shows a clear and consistent winner across both tested workloads. The NVIDIA Tesla K80 outperforms the NVIDIA T400 4 GB in every single metric available in the database, with the gap widening considerably depending on the API used.

In the Geekbench OpenCL test, the Tesla K80 scores 18,620 points against 17,320 points for the T400 4 GB. This represents a 7.5% advantage for the older Tesla card. While this is a meaningful lead, it is not an overwhelming one. The delta suggests that in compute workloads that scale well with raw shader throughput, the K80's massive shading unit count (2,496 versus 384) provides a solid edge, but the T400's much higher boost clock partially compensates for its smaller chip.

The Vulkan benchmark tells a different and more decisive story. Here, the Tesla K80 posts a score of 19,111, while the T400 4 GB manages only 16,263. The delta expands to 17.5% in favor of the K80. This larger margin indicates that the K80's architecture handles the Vulkan workload more efficiently, likely due to its higher memory bandwidth (240.6 GB/s versus 80.00 GB/s) and wider 384-bit bus, which reduces pressure on the memory subsystem during graphics-heavy tasks.

Looking at the broader database context, the K80's average benchmark score of 18,866 places it in the 63rd percentile of all GPUs. Its nearest rivals, according to the database, include the NVIDIA GeForce RTX 2070 (average score 18,789, a 0.4% delta) and the NVIDIA RTX 2000 Ada Generation (average score 18,954, a -0.5% delta). This means the K80 sits in a tight cluster of cards with nearly identical average performance, despite its age. The T400 4 GB, with an average score of 16,792, sits in the 60th percentile, and its closest competitor is the AMD Radeon RX 7600S (16,696 average, 0.6% delta). The T400 is also near the NVIDIA Tesla M4 (16,932, -0.8% delta), which is a notable comparison since the M4 is a different Tesla-generation product.

The head-to-head results are unambiguous: the K80 wins both tests, securing 2 wins out of 2 possible. The T400 4 GB records zero wins. There is no test in the database where the T400 pulls ahead, and the largest single-test margin is the 17.5% Vulkan gap. This is a decisive result, but it is worth examining why the K80, a card from the Kepler era, maintains such a lead over a much newer Turing-based product.

Where Each One Wins

Based strictly on the benchmark wins, the NVIDIA Tesla K80 is the superior compute performer in both OpenCL and Vulkan. Its wins are not narrow squeaks; the Vulkan result is a substantial 17.5% margin. The K80's advantage likely stems from its dual-GPU design philosophy, where raw throughput and memory bandwidth are prioritized over efficiency or display features. In the database, the K80's average score of 18,866 is roughly 12.4% higher than the T400's 16,792, which is a significant gap when translated into real-world task completion times for compute-heavy workloads.

The T400 4 GB, however, has its own domain where it excels, and that is not reflected in the raw benchmark scores. The T400's specifications reveal a different intended use case. It features 4 GB of GDDR6 memory on a 64-bit bus, a single-slot design, no power connectors, a 30 W TDP, and a suggested PSU of only 200 W. It also includes 3x mini-DisplayPort 1.4a outputs. This is a card designed for low-power, display-centric environments, not for heavy compute. The K80, by contrast, has no display outputs, a 300 W TDP, requires a 1x 8-pin power connector, and a 700 W suggested PSU. It is a pure compute accelerator.

So, while the T400 loses every benchmark, it wins on power efficiency and physical footprint. The data shows a 270 W difference in TDP (300 W versus 30 W), and the T400 occupies a single slot versus the K80's dual-slot design. For a workstation that needs to drive multiple monitors with minimal power draw, the T400 is the only viable choice from these two options. For any task that involves compute acceleration, the K80 is the clear winner based on the benchmark results. The database does not record any benchmark where the T400's lower power draw translates into a performance win, so the use-case split is stark: compute performance goes to the K80, while low-power display output goes to the T400.

Architecture Differences

The two cards are separated by two generations of NVIDIA architecture, and the differences are profound. The Tesla K80 is built on the Kepler 2.0 architecture, specifically using the GK210 chip. It is manufactured on a 28 nm process at TSMC, with a massive 7,100 million transistors on a 561 mm² die. This results in a transistor density of 12.7 million transistors per mm². The K80's base clock is 562 MHz, with a boost clock of 824 MHz. Its memory runs at 1253 MHz, which translates to 5 Gbps effective, across a 384-bit bus, yielding 240.6 GB/s of bandwidth. The card has 2,496 shading units, 208 texture mapping units, and 48 raster operation units. Its pixel rate is 42.85 GPixel/s, and its texture rate is 171.4 GTexel/s. FP32 performance is rated at 4.113 TFLOPS. It supports DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.175.

The T400 4 GB, on the other hand, is based on the Turing architecture, using the TU117 chip. This is a 12 nm TSMC part with 4,700 million transistors on a 200 mm² die, giving a much higher transistor density of 23.5 million per mm². The base clock is 420 MHz, but the boost clock is 1425 MHz, which is significantly higher than the K80's boost. Memory runs at 1250 MHz, or 10 Gbps effective, on a 64-bit bus, providing 80.00 GB/s of bandwidth. The T400 has 384 shading units, 24 TMUs, and 16 ROPs. Its pixel rate is 22.80 GPixel/s, and texture rate is 34.20 GTexel/s. FP32 performance is 1,094.4 GFLOPS, and it supports FP16 at 2.189 TFLOPS with a 2:1 ratio. It supports DirectX 12 (12_1), OpenGL 4.6, and Vulkan 1.4.

The architectural chasm is evident in several key metrics. The K80 has 6.5 times more shading units (2,496 versus 384). Its memory bandwidth is exactly three times higher (240.6 GB/s versus 80.00 GB/s). The K80's FP32 throughput is roughly 3.8 times that of the T400 (4.113 TFLOPS versus 1.0944 TFLOPS). However, the T400 wins on clock speed, with a 1425 MHz boost versus 824 MHz, and it supports a newer DirectX version (12_1 versus 11_1) and a newer Vulkan version (1.4 versus 1.2.175). The T400 also has FP16 support, which the K80 lacks entirely. The memory types differ as well: K80 uses GDDR5, while T400 uses GDDR6. The T400 is also dramatically more power-efficient on paper, with a 30 W TDP versus 300 W, and it does not require any external power connectors, whereas the K80 needs a single 8-pin connector.

FAQ

Q: Which GPU has higher raw FP32 compute performance?

A: The NVIDIA Tesla K80 has an FP32 rating of 4.113 TFLOPS, while the NVIDIA T400 4 GB is rated at 1,094.4 GFLOPS. The K80 is approximately 3.8 times faster in this metric.

Q: What is the memory bandwidth difference between the two cards?

A: The K80 has a memory bandwidth of 240.6 GB/s, using a 384-bit bus with GDDR5 memory. The T400 4 GB has 80.00 GB/s, using a 64-bit bus with GDDR6 memory. The K80 offers exactly three times the bandwidth.

Q: Which card supports newer graphics APIs?

A: The T400 4 GB supports DirectX 12 (12_1) and Vulkan 1.4, while the K80 supports DirectX 12 (11_1) and Vulkan 1.2.175. The T400 is the newer API implementation.

Q: How do their power requirements compare?

A: The T400 4 GB has a TDP of 30 W and requires no power connectors, with a suggested PSU of 200 W. The K80 has a TDP of 300 W, requires a single 8-pin power connector, and suggests a 700 W PSU.

Q: Which card has display outputs?

A: Only the T400 4 GB has display outputs, with 3x mini-DisplayPort 1.4a. The Tesla K80 has no display outputs and is designed for compute-only workloads.

Q: What are the average benchmark scores for each card?

A: The K80 has an average benchmark score of 18,866, while the T400 4 GB has an average of 16,792. The K80 is about 12.4% higher in this aggregate metric.

The Verdict

The benchmark data is unambiguous: the NVIDIA Tesla K80 is the superior performer in every recorded test. It wins both the OpenCL and Vulkan benchmarks, with deltas of 7.5% and 17.5% respectively. Its average benchmark score of 18,866 places it in the 63rd percentile of all GPUs, and it trades blows with cards like the RTX 2070 and RTX 2000 Ada Generation, which are much newer products. For any compute workload that relies on OpenCL or Vulkan, the K80 is the clear choice.

However, the verdict is not a simple recommendation for all users. The T400 4 GB is a fundamentally different kind of product. With a 30 W TDP, no power connectors, and 3x mini-DisplayPort outputs, it is designed for low-power workstations where display output is required and compute is secondary. Its 80.00 GB/s bandwidth and 384 shading units are modest, but its 1425 MHz boost clock and newer architecture (Turing versus Kepler) make it a capable card for light tasks. The K80's 300 W TDP, dual-slot design, and absence of display outputs make it wholly unsuitable for such environments.

The data suggests a clear split: if the task is compute acceleration, the K80 wins decisively, and its 17.5% Vulkan lead is the strongest evidence. If the task is power-efficient display output, the T400 is the only option, and its 4 GB of GDDR6 memory is adequate for that role. The K80's 12 GB of GDDR5 is overkill for display work but essential for large compute datasets. In the end, the K80 is the benchmark champion, but the T400 wins on efficiency and form factor. Choose based on workload, not on raw scores alone.