AMD Radeon HD 7790 vs NVIDIA Tesla K20m Comparison

The NVIDIA Tesla K20m and AMD Radeon HD 7790 are two end-of-life GPUs from 2013 that occupy very different positions in the hardware landscape, and the benchmark data reflects this clearly. The Tesla K20m, a professional compute card with a 64th percentile ranking, delivers an average benchmark score of 19,089, placing it in a dead heat with modern mainstream parts like the GeForce RTX 4050 Mobile and Radeon RX 6600. The Radeon HD 7790, a consumer gaming card, scores 17,666 on average, sitting at the 61st percentile and trailing the Tesla by 1,423 points, a gap that represents roughly an 8% advantage for the NVIDIA part. Despite having no direct head-to-head benchmark results, the aggregate data and percentile positions tell a clear story of a compute-oriented heavyweight beating a compact consumer card in raw throughput.

Head-to-Head Benchmarks

The most striking difference in the data is the sheer scale of the performance gap between these two cards. The Tesla K20m’s average benchmark score of 19,089 is substantially higher than the Radeon HD 7790’s 17,666, a difference of 1,423 points. This translates to the Tesla being approximately 8% faster on average, a meaningful margin that is consistent across the available benchmark types. The Tesla’s nearest rivals include the GeForce GTX 780 (19,164, -0.4% delta), which actually edges it out slightly, and the Quadro K6000 (19,030, +0.3% delta), which is nearly identical in performance. This shows the K20m is firmly in the company of high-end desktop and professional GPUs, not mid-range consumer parts.

The Radeon HD 7790, by contrast, sits in a lower performance tier. Its average score of 17,666 is closest to the GeForce RTX 4060 (17,639, +0.2% delta) and the Radeon 780M (17,588, +0.4% delta), both of which are much newer integrated or entry-level discrete solutions. The fact that a 2013 card is competitive with these modern parts is notable, but it also underscores that the HD 7790 was never intended to compete with the Tesla K20m. The Tesla’s advantage in compute workloads is even more pronounced when considering its raw specifications: it boasts 2,496 shading units versus the HD 7790’s 896, and a memory bandwidth of 208.0 GB/s versus the AMD card’s 96.00 GB/s. These are not subtle differences; they represent a fundamental gap in processing capability.

Looking at specific benchmark entries, the Tesla K20m shows its strength in OpenCL and Vulkan tests, scoring 16,241 and 21,936 respectively. The Vulkan score in particular is impressive, nearly matching the average of its closest rival, the GTX 780. The Radeon HD 7790 only has a single benchmark entry — a Metal score of 17,666 — which happens to equal its average. This lack of cross-platform benchmark data makes direct comparison difficult, but the overall average score is the best available metric, and it clearly favors the NVIDIA card. The percentile rankings reinforce this: the Tesla is at the 64th percentile of all GPUs, while the HD 7790 is at the 61st, a gap that may seem small but is meaningful over a large sample of hardware.

Where Each One Wins

The Tesla K20m wins decisively in any scenario that demands raw compute throughput. With 3.524 TFLOPS of FP32 performance, it more than doubles the Radeon HD 7790’s 1.792 TFLOPS. This makes the Tesla the obvious choice for scientific computing, machine learning inference, or any professional workload that leverages OpenCL or Vulkan compute. Its 5 GB of GDDR5 memory, paired with a 320-bit bus, provides 208.0 GB/s of bandwidth, which is crucial for large datasets that would quickly exhaust the HD 7790’s 1 GB frame buffer. The Tesla also achieves a pixel rate of 36.71 GPixel/s and a texture rate of 146.8 GTexel/s, both roughly double the HD 7790’s 16.00 GPixel/s and 56.00 GTexel/s. For any task that is memory-bound or shader-heavy, the Tesla is in a different league.

The Radeon HD 7790’s wins are less about raw performance and more about efficiency and practical deployment. Its 85 W TDP is dramatically lower than the Tesla’s 225 W, and it requires only a 250 W suggested power supply versus the Tesla’s 550 W. This makes the HD 7790 a viable option for small form factor builds or systems with modest power budgets. It also has a PCIe 3.0 x16 interface, which is a generation newer than the Tesla’s PCIe 2.0 x16, potentially offering better bandwidth in compatible systems. Furthermore, the HD 7790 has actual display outputs — 1x DVI, 1x HDMI 1.4a, and 2x mini-DisplayPort 1.2 — while the Tesla K20m has no display outputs at all, making it useless as a standalone graphics card for a desktop. For a user who needs a functional GPU for everyday tasks with some gaming capability, the HD 7790 is the only option of the two.

FAQ

Q: Which GPU has a higher average benchmark score?

A: The NVIDIA Tesla K20m has an average benchmark score of 19,089, which is 1,423 points higher than the AMD Radeon HD 7790’s average of 17,666.

Q: How does the Tesla K20m compare to its nearest rivals?

A: The Tesla K20m’s average score of 19,089 is within 0.4% of the NVIDIA GeForce GTX 780 (19,164) and within 0.3% of the AMD Radeon RX 6600 (19,036), indicating it performs at a level comparable to these modern GPUs.

Q: What is the Radeon HD 7790 closest to in performance?

A: The Radeon HD 7790’s average score of 17,666 is most closely matched by the NVIDIA GeForce RTX 4060, which scores 17,639, a delta of just 0.2%. It is also within 0.4% of the AMD Radeon 780M’s score of 17,588.

Q: Which card has more memory bandwidth?

A: The Tesla K20m has 208.0 GB/s of memory bandwidth, which is more than double the Radeon HD 7790’s 96.00 GB/s. This is due to the Tesla’s wider 320-bit memory bus compared to the HD 7790’s 128-bit bus.

Q: Can either card be used for display output?

A: The AMD Radeon HD 7790 has display outputs (1x DVI, 1x HDMI 1.4a, 2x mini-DisplayPort 1.2), while the NVIDIA Tesla K20m has no display outputs, meaning it requires a separate graphics adapter for any visual output.

Q: What is the difference in power consumption?

A: The Radeon HD 7790 has a TDP of 85 W with a suggested PSU of 250 W, while the Tesla K20m has a TDP of 225 W and requires a 550 W suggested power supply.

Specification Differences

The two cards differ in nearly every measurable specification. The Tesla K20m uses a 5 GB GDDR5 memory configuration with a 320-bit bus, yielding 208.0 GB/s of bandwidth. The Radeon HD 7790 has just 1 GB of GDDR5 memory on a 128-bit bus, providing 96.00 GB/s. The Tesla has 2,496 shading units, 208 TMUs, and 40 ROPs, while the HD 7790 has 896 shading units, 56 TMUs, and 16 ROPs. Peak FP32 performance is 3.524 TFLOPS for the Tesla versus 1.792 TFLOPS for the AMD card. Pixel and texture rates are 36.71 GPixel/s and 146.8 GTexel/s for the Tesla, compared to 16.00 GPixel/s and 56.00 GTexel/s for the HD 7790.

The memory clock also differs: the Tesla runs at 1300 MHz (5.2 Gbps effective), while the HD 7790 runs at 1500 MHz (6 Gbps effective). Despite the higher memory clock on the AMD card, the Tesla’s wider bus gives it vastly superior bandwidth. The bus interface is different as well: the Tesla uses PCIe 2.0 x16, while the HD 7790 uses PCIe 3.0 x16. Power requirements are starkly different: the Tesla has a 225 W TDP and needs both a 6-pin and 8-pin power connector, while the HD 7790 has an 85 W TDP and only a single 6-pin connector. The cards also differ in physical dimensions: the Tesla is 267 mm (10.5 inches) long, while the HD 7790 is a more compact 183 mm (7.2 inches). Launch MSRP for the Tesla was 3,199 USD, while the HD 7790 launched at 149 USD.

Architecture Differences

The architectural divide is fundamental. The Tesla K20m is built on NVIDIA’s Kepler architecture with the GK110 chip, which is a large, compute-optimized design. It contains 7,080 million transistors on a 561 mm² die, fabricated on TSMC’s 28 nm process, giving a transistor density of 12.6M / mm². The Radeon HD 7790 uses AMD’s GCN 2.0 architecture with the Bonaire chip, a much smaller design with 2,080 million transistors on a 160 mm² die, also on TSMC’s 28 nm process, achieving a slightly higher transistor density of 13.0M / mm². The generation names reflect their different lineages: the Tesla is part of the “Tesla Kepler (Kxx)” generation, while the HD 7790 belongs to the “Southern Islands (HD 7700)” generation.

Neither card has ray tracing cores or tensor cores, which is expected for 2013-era hardware. The API support differs slightly: the Tesla supports DirectX 12 (11_0), OpenGL 4.6, and Vulkan 1.2.175, while the HD 7790 supports DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.2.170. The DirectX 12 feature level is higher on the AMD card (12_0 vs 11_0), which may matter for certain modern gaming titles. In terms of product lineage, the Tesla’s predecessor is Tesla Fermi and its successor is Tesla Maxwell, while the HD 7790’s predecessor is Northern Islands and its successor is Sea Islands. These architectural differences explain the performance gap: the Tesla is a massive compute chip designed for maximum throughput, while the HD 7790 is a smaller, power-efficient chip aimed at mainstream gaming.

The Verdict

The data is unambiguous: choose the NVIDIA Tesla K20m if your priority is raw compute performance. It delivers an 8% higher average benchmark score (19,089 vs 17,666), more than double the FP32 throughput (3.524 TFLOPS vs 1.792 TFLOPS), and over twice the memory bandwidth (208.0 GB/s vs 96.00 GB/s). Its 5 GB memory capacity is five times that of the HD 7790, making it suitable for large-scale professional workloads. The fact that it sits in the same performance class as the GeForce RTX 4050 Mobile and Radeon RX 6600, despite being a decade old, speaks to its compute pedigree. However, it is absolutely unsuitable for desktop use, as it has no display outputs, requires a 550 W power supply, and consumes 225 W.

Choose the AMD Radeon HD 7790 if you need a functional, efficient GPU for a standard desktop. It has display outputs, a much lower 85 W TDP, and only needs a 250 W power supply. Its 61st percentile ranking and average score of 17,666 make it competitive with modern entry-level parts like the Radeon 780M, which is remarkable for a 2013 card. The HD 7790 also offers a higher DirectX 12 feature level (12_0) and a PCIe 3.0 interface. For gaming on a legacy system or a low-power build, the HD 7790 is the only viable option. For any serious compute task, the Tesla K20m is the clear winner, provided you have the power budget and a separate display adapter. The verdict is simple: the Tesla is a compute workhorse, the HD 7790 is a practical consumer card, and they should not be cross-shopped for the same use case.