NVIDIA Tesla K40m vs NVIDIA Tesla M4 Comparison

The NVIDIA Tesla K40m wins this matchup decisively in the recorded data, taking the only head-to-head benchmark by a wide margin while offering far greater compute and memory resources. The Tesla M4 counters with dramatically lower power draw and a newer feature set, making this a classic throughput-versus-efficiency split between two end-of-life data center accelerators.

Head-to-Head Benchmarks

The database contains a single head-to-head result, and it leaves no ambiguity. In the Geekbench OpenCL test the Tesla K40m scores 19885 against 16932 for the Tesla M4, a 17.4 percent advantage for the Kepler-based card. That gap is substantial: the M4 would need well over 2900 additional points to close it.

Context from the broader database sharpens the picture. The K40m sits in the 65th percentile of all GPUs measured, and its score places it essentially dead level with its nearest rivals, among them the AMD FirePro W7000 at 19905 (just 0.1 percent ahead of the K40m) and ahead of the AMD Radeon RX 6650 XT at 19765 (0.6 percent behind), the AMD FirePro D300 at 19637 (1.3 percent behind), and the NVIDIA Quadro K5200 at 19602 (1.4 percent behind). In other words, the K40m trades blows with a mixed field of professional and consumer cards.

The M4's 16932 score puts it in the 60th percentile, five points lower. Its own rival cluster is instructive: the AMD Radeon HD 7970M scores 17019, 0.5 percent ahead; the NVIDIA GeForce GTX 690 scores 17037, 0.6 percent ahead; the NVIDIA T400 4 GB scores 16792, 0.8 percent behind; and the AMD Radeon RX 7600 XT scores 17083, 0.9 percent ahead. Every one of those rivals edges past the M4 except the T400, reinforcing that the K40m operates a full tier above it in measured throughput.

Where Each One Wins

The K40m wins wherever raw throughput and capacity dominate the workload. Its FP32 compute stands at 5.046 TFLOPS versus 2.195 TFLOPS for the M4, more than double the output. Texture fill rate favors the K40m 210.2 GTexel/s to 68.61 GTexel/s, and pixel fill rate goes to it as well, 52.56 GPixel/s against 34.30 GPixel/s. For memory-bound workloads the difference is even starker: 12 GB of GDDR5 on a 384-bit bus delivering 288.4 GB/s, compared with 4 GB on a 128-bit bus delivering 88.00 GB/s. That is over three times the bandwidth and three times the capacity, which matters for large datasets that cannot fit in the M4's smaller frame buffer.

The M4 wins on efficiency and platform footprint. Its TDP is 50 W versus 245 W for the K40m, roughly one fifth of the power. It is a single-slot card where the K40m is dual-slot, and the suggested power supply is a modest 250 W against 550 W for the K40m. In dense server deployments where board area, thermals, and power allocation are the binding constraints, the M4 is the practical fit; the recorded data simply shows it delivers much less performance per card doing so.

Architecture Differences

Both cards come from NVIDIA and both are fabricated by TSMC on a 28 nm process, but they represent consecutive accelerator generations. The K40m is built on the GK110B chip of the Kepler architecture, part of the Tesla Kxx generation, and succeeds the Tesla Fermi line. The M4 uses the GM206 chip of Maxwell 2.0, part of the Tesla Mxx generation, and succeeds Tesla Kepler directly before handing off to Tesla Pascal.

The silicon scale is very different. The GK110B die measures 561 mm² and packs 7080 million transistors, a density of 12.6M per mm². The GM206 die is 228 mm² with 2940 million transistors at 12.9M per mm². The K40m's much larger die funds 2880 shading units, 240 TMUs, and 48 ROPs, dwarfing the M4's 1024 shading units, 64 TMUs, and 32 ROPs.

Clocking runs the other way, as the smaller Maxwell chip boosts higher: 872 MHz base and 1072 MHz boost for the M4 against 745 MHz base and 876 MHz boost for the K40m. The K40m's memory runs at 1502 MHz (6 Gbps effective) versus 1375 MHz (5.5 Gbps effective) for the M4, but the bus width difference of 384-bit versus 128-bit is what drives the bandwidth gap.

The newer generation also carries newer software interfaces. The M4 supports DirectX 12 at feature level 12_1 and Vulkan 1.4, while the K40m supports DirectX 12 at feature level 11_1 and Vulkan 1.2.175; both support OpenGL 4.6. Neither card has RT cores or tensor cores. Neither offers display outputs, confirming their headless accelerator role. The K40m measures 267 mm (10.5 inches) in length; the M4's dimensions are not recorded in the database.

The Verdict

Based strictly on the recorded data, the Tesla K40m is the performance pick. It wins the only head-to-head benchmark by 17.4 percent, delivers over twice the FP32 throughput, and triples both memory capacity and bandwidth. Workloads that saturate a GPU benefit from every one of those advantages.

The Tesla M4 is the right choice when power and space are the limiting factors, not speed. At 50 W in a single slot, it fits where the 245 W dual-slot K40m cannot, and it carries the newer DirectX and Vulkan support of its Maxwell 2.0 generation. Buyers choosing on absolute capability should take the K40m; buyers choosing on deployment constraints should take the M4 and accept the measured performance deficit. Both cards are end-of-life, so either selection is a legacy-platform decision.

FAQ

Q: Which card is faster in benchmarks?

A: The Tesla K40m. It scores 19885 in Geekbench OpenCL versus 16932 for the Tesla M4, a 17.4 percent lead, and it sits in the 65th percentile of all GPUs versus the M4's 60th.

Q: How much more compute does the K40m offer?

A: The K40m delivers 5.046 TFLOPS FP32 against the M4's 2.195 TFLOPS, more than double the throughput.

Q: How do their memory configurations compare?

A: The K40m has 12 GB of GDDR5 on a 384-bit bus with 288.4 GB/s of bandwidth. The M4 has 4 GB of GDDR5 on a 128-bit bus with 88.00 GB/s.

Q: What is the power difference?

A: The M4 draws 50 W and suggests a 250 W power supply; the K40m draws 245 W and suggests a 550 W unit.

Q: Do both cards support the same graphics APIs?

A: No. The M4 supports DirectX 12 (12_1) and Vulkan 1.4, while the K40m supports DirectX 12 (11_1) and Vulkan 1.2.175. Both support OpenGL 4.6.

Q: Which rival GPUs score similarly to these cards?

A: The K40m lands within roughly one percent of the AMD FirePro W7000, AMD Radeon RX 6650 XT, AMD FirePro D300, and NVIDIA Quadro K5200. The M4 clusters with the AMD Radeon HD 7970M, NVIDIA GeForce GTX 690, NVIDIA T400 4 GB, and AMD Radeon RX 7600 XT.

Specification Differences

| Specification | NVIDIA Tesla K40m | NVIDIA Tesla M4 |

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

| Chip | GK110B | GM206 |

| Architecture | Kepler | Maxwell 2.0 |

| Generation | Tesla Kepler (Kxx) | Tesla Maxwell (Mxx) |

| Transistors | 7,080 million | 2,940 million |

| Die size | 561 mm² | 228 mm² |

| Transistor density | 12.6M / mm² | 12.9M / mm² |

| Base clock | 745 MHz | 872 MHz |

| Boost clock | 876 MHz | 1072 MHz |

| Memory clock | 1502 MHz (6 Gbps effective) | 1375 MHz (5.5 Gbps effective) |

| Memory size | 12 GB | 4 GB |

| Bus width | 384 bit | 128 bit |

| Bandwidth | 288.4 GB/s | 88.00 GB/s |

| Shading units | 2880 | 1024 |

| TMUs | 240 | 64 |

| ROPs | 48 | 32 |

| Pixel rate | 52.56 GPixel/s | 34.30 GPixel/s |

| Texture rate | 210.2 GTexel/s | 68.61 GTexel/s |

| FP32 | 5.046 TFLOPS | 2.195 TFLOPS |

| TDP | 245 W | 50 W |

| Slot width | Dual-slot | Single-slot |

| Suggested PSU | 550 W | 250 W |

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

| Vulkan | 1.2.175 | 1.4 |

| Length | 267 mm (10.5 inches) | Not recorded |

| Release date | November 2013 | November 2015 |

| Predecessor | Tesla Fermi | Tesla Kepler |

| Successor | Tesla Maxwell | Tesla Pascal |

| Launch MSRP | 7,699 USD | Not recorded |

| Percentile vs all GPUs | 65 | 60 |