AMD Radeon HD 7790 vs NVIDIA Tesla K40m Comparison

The NVIDIA Tesla K40m and AMD Radeon HD 7790 are two End-of-life 28 nm TSMC parts built for entirely different jobs, and the database data makes the split unambiguous: the K40m is a 12 GB passive-compute accelerator with 5.046 TFLOPS of FP32 throughput, while the HD 7790 is a compact 85 W graphics card with 1.792 TFLOPS. Neither card's compute result dominates the other by a wide margin on paper, but their designs, memory capacities, and output configurations point at completely separate user cases.

The Verdict

The Tesla K40m is the pick when memory capacity and sustained compute matter most. Its 12 GB of GDDR5 across a 384-bit bus delivers 288.4 GB/s of bandwidth, three times the 96 GB/s of the HD 7790, and its 2880 shading units, 240 TMUs, and 48 ROPs outnumber the smaller card's 896, 56, and 16 by roughly three to one in every case. The HD 7790 is the pick when the goal is a display-capable card with modest power needs: it carries DVI, HDMI 1.4a, and two mini-DisplayPort 1.2 outputs where the K40m has none, and its 85 W TDP and 250 W suggested PSU sit far below the K40m's 245 W TDP and 550 W suggested PSU. The database records a Geekbench OpenCL score of 19885 for the K40m against a Geekbench Metal score of 17666 for the HD 7790, placing the K40m at the 65th percentile of all GPUs and the 7790 at the 61st, but these results come from different tests, so the recorded data should be read as context rather than a direct race.

Architecture Differences

Both cards were fabricated on TSMC's 28 nm process, and that is where the similarities end. The K40m uses NVIDIA's Kepler architecture on the GK110B die, part of the Tesla Kepler (Kxx) generation, with 7080 million transistors packed into a 561 mm² die, a density of 12.6M per mm². The HD 7790 uses AMD's GCN 2.0 architecture on the Bonaire die within the Southern Islands (HD 7700) generation, with 2080 million transistors on a 160 mm² die at 13.0M per mm². The transistor budgets differ by more than a factor of three, and the functional counts follow: 2880 shading units versus 896, 240 TMUs versus 56, and 48 ROPs versus 16.

Clock behavior also differs. The K40m lists a 745 MHz base and 876 MHz boost clock, while the HD 7790's core clocks are not recorded in the database, though its memory runs at 1500 MHz, effectively 6 Gbps, nearly identical to the K40m's 1502 MHz memory clock at the same effective 6 Gbps. The HD 7790 claims a slightly higher DirectX feature level, 12 (12_0) versus the K40m's 12 (11_1), while the K40m edges ahead in Vulkan support at 1.2.175 versus 1.2.170; both report OpenGL 4.6. The two cards also sit at different lineage points: the K40m succeeded Tesla Fermi and was followed by Tesla Maxwell, whereas the HD 7790 followed Northern Islands and was succeeded by Sea Islands. Both connect over PCIe 3.0 x16 and occupy dual-slot envelopes, though at 267 mm long the K40m is considerably larger than the 183 mm HD 7790. Neither card carries RT cores or tensor cores.

FAQ

Q: Which card has the higher compute benchmark score in the database?

A: The Tesla K40m recorded 19885 in Geekbench OpenCL, while the HD 7790 recorded 17666 in Geekbench Metal. The tests differ, so the numbers are context rather than a strict head-to-head result.

Q: How do the two compare against all GPUs in the database?

A: The K40m sits at the 65th percentile versus all GPUs, and the HD 7790 at the 61st, a four-point gap in the K40m's favor.

Q: Which card can drive a display?

A: Only the HD 7790. It offers one DVI output, one HDMI 1.4a output, and two mini-DisplayPort 1.2 outputs. The Tesla K40m has no display outputs at all, consistent with its role as a compute accelerator.

Q: How much memory does each card have, and what bandwidth does it provide?

A: The K40m has 12 GB of GDDR5 on a 384-bit bus delivering 288.4 GB/s. The HD 7790 has 1024 MB of GDDR5 on a 128-bit bus delivering 96.00 GB/s. That is a twelvefold capacity advantage for the K40m and exactly three times the bandwidth.

Q: What power does each card require?

A: The K40m has a 245 W TDP and a 550 W suggested PSU. The HD 7790 has an 85 W TDP, a 250 W suggested PSU, and a single 6-pin power connector.

Q: When were these cards released and what did they cost at launch?

A: The K40m was released on 21 November 2013 with a launch MSRP of 7,699 USD. The HD 7790 was released on 21 March 2013 with a launch MSRP of 149 USD.

Specification Differences

| Field | Tesla K40m | Radeon HD 7790 |

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

| Chip | GK110B | Bonaire |

| Architecture | Kepler | GCN 2.0 |

| Generation | Tesla Kepler (Kxx) | Southern Islands (HD 7700) |

| Transistors | 7080 million | 2080 million |

| Die size | 561 mm² | 160 mm² |

| Transistor density | 12.6M / mm² | 13.0M / mm² |

| Base / boost clock | 745 MHz / 876 MHz | not recorded |

| Memory size | 12 GB | 1024 MB |

| Bus width | 384 bit | 128 bit |

| Bandwidth | 288.4 GB/s | 96.00 GB/s |

| Shading units | 2880 | 896 |

| TMUs | 240 | 56 |

| ROPs | 48 | 16 |

| Pixel rate | 52.56 GPixel/s | 16.00 GPixel/s |

| Texture rate | 210.2 GTexel/s | 56.00 GTexel/s |

| FP32 | 5.046 TFLOPS | 1.792 TFLOPS |

| TDP | 245 W | 85 W |

| Suggested PSU | 550 W | 250 W |

| Power connectors | not recorded | 1x 6-pin |

| Display outputs | No outputs | 1x DVI, 1x HDMI 1.4a, 2x mini-DisplayPort 1.2 |

| DirectX | 12 (11_1) | 12 (12_0) |

| Vulkan | 1.2.175 | 1.2.170 |

| Length | 267 mm (10.5 in) | 183 mm (7.2 in) |

| Release date | 21 November 2013 | 21 March 2013 |

| Launch MSRP | 7,699 USD | 149 USD |

Both share a 28 nm TSMC process node, GDDR5 memory at an effective 6 Gbps, a dual-slot width, and PCIe 3.0 x16, so those fields do not separate the two.

Head-to-Head Benchmarks

The database contains no shared head-to-head benchmark entries for this pair, with zero recorded wins on either side. What the data does provide is a single benchmark result per card from different tests, plus percentile context. The K40m's 19885 Geekbench OpenCL score places it at the 65th percentile of all GPUs, and its nearest rivals cluster remarkably tightly: the AMD FirePro W7000 sits just 0.1 percent ahead at 19905, the AMD Radeon RX 6650 XT sits 0.6 percent behind at 19765, the AMD FirePro D300 is 1.3 percent behind at 19637, and the NVIDIA Quadro K5200 trails by 1.4 percent at 19602. In other words, the K40m lands in a statistical dead heat with professional cards and a much later consumer card in the database rankings.

The HD 7790's 17666 Geekbench Metal score puts it at the 61st percentile, in an equally tight neighborhood: the NVIDIA GeForce RTX 4060 at 17639 is 0.2 percent behind, the AMD Radeon 780M at 17588 is 0.4 percent behind, the AMD Radeon Pro 560 at 17551 trails by 0.7 percent, and the NVIDIA Quadro RTX 4000 at 17789 is 0.7 percent ahead. Both cards therefore occupy similar relative positions in the database, but because the tests and rival sets differ, no direct conclusion about relative compute performance can be drawn from these figures alone. The theoretical specifications are the clearer separator: the K40m's 5.046 TFLOPS of FP32 compute is 2.8 times the HD 7790's 1.792 TFLOPS, matching the ratios seen in shading units, TMUs, ROPs, and memory bandwidth.

Where Each One Wins

The Tesla K40m wins on every dimension of raw throughput and capacity. It delivers 5.046 TFLOPS FP32 against 1.792, 210.2 GTexel/s of texture throughput against 56.00, and 52.56 GPixel/s of pixel throughput against 16.00. Its 12 GB memory pool and 288.4 GB/s bandwidth make it the only option of the two for workloads that need large datasets resident on the card, and its 65th percentile database placement, essentially level with cards like the FirePro W7000 and Quadro K5200, reflects that compute focus. It is the card for GPU compute, not for a desktop.

The Radeon HD 7790 wins on usability and efficiency. It draws 85 W against 245 W, needs a 250 W suggested PSU against 550 W, fits in a 183 mm length against 267 mm, and offers four display outputs against none. Its higher DirectX feature level of 12_0 versus 11_1 also gives it the more modern graphics API baseline for rendering work. It is the card for a small display-capable system with modest power delivery, where the K40m simply cannot serve because it has no outputs at all. The recorded data leaves no ambiguity: compute goes to the K40m, graphics goes to the HD 7790, and nothing in the two benchmark sets contradicts that split.