AMD Radeon R7 M260 vs NVIDIA GeForce GT 645M Comparison

The AMD Radeon R7 M260 and NVIDIA GeForce GT 645M are both end-of-life mobile graphics solutions from the 28 nm era, targeting similar performance tiers. The data shows a clear split: the R7 M260 leads in both shared benchmark tests, while the GT 645M counters with a higher average score in a platform-specific test and a lower power draw. This analysis breaks down the benchmark results, architectural differences, and specification gaps to determine where each part holds an advantage.

Where Each One Wins

The benchmark results indicate that the AMD Radeon R7 M260 is the stronger performer in cross-platform compute workloads. In the Geekbench OpenCL test, the R7 M260 scores 3708 against the GT 645M’s 2680, a decisive 38.4% advantage. In the Vulkan test, the AMD part again wins, posting 5289 versus 4875, an 8.5% lead. These are the only two head-to-head tests where both GPUs have scores, and AMD wins both.

The NVIDIA GeForce GT 645M’s sole victory comes from a test the R7 M260 does not participate in: Geekbench Metal, where it scores 5679. This is a macOS-specific API, and the AMD part has no corresponding entry in the data. Therefore, the GT 645M’s win is confined to that ecosystem. Additionally, the GT 645M has a lower TDP of 32 W, which is a meaningful advantage for thin-and-light laptops, though the R7 M260’s TDP is not listed in the pack.

The wins break down as 2 for the AMD part and 0 for the NVIDIA part in shared tests. However, the GT 645M’s Metal score suggests it may be the better choice for users prioritizing Apple-centric workloads, provided the rest of the system supports it.

Architecture Differences

The two GPUs come from different architectural lineages. The AMD Radeon R7 M260 is built on GCN 3.0, using the Topaz chip, while the NVIDIA GeForce GT 645M uses the Kepler architecture with the GK107 chip. Both are fabricated on a 28 nm process at TSMC, but the transistor counts differ: AMD packs 1,550 million transistors into a 125 mm² die, yielding a density of 12.4M transistors per mm². NVIDIA’s chip has 1,270 million transistors on a 118 mm² die, for a density of 10.8M per mm². The AMD chip is therefore denser, which partially explains its higher clock-for-clock compute output.

Clock speeds also diverge. The R7 M260 runs at a base of 940 MHz with a boost of 980 MHz, while the GT 645M is slower at 709 MHz base and 780 MHz boost. Memory clocks are identical at 900 MHz (1800 Mbps effective), but the memory subsystems differ: both use 2 GB of DDR3, yet the AMD part has a 64-bit bus (14.40 GB/s bandwidth) versus NVIDIA’s 128-bit bus (28.80 GB/s). The GT 645M has double the memory bandwidth, which is a significant architectural advantage.

Shader configurations are similar in count but not in layout. Both have 384 shading units, but the R7 M260 has 24 TMUs and 8 ROPs, while the GT 645M has 32 TMUs and 16 ROPs. This means the NVIDIA part has more texture and pixel throughput capability per clock, despite its lower core clocks. API support also differs: the R7 M260 supports DirectX 12 (12_0), while the GT 645M supports DirectX 12 (11_0). Vulkan versions are close (1.2.170 vs 1.2.175), and both support OpenGL 4.6. The bus interface is another split: the R7 M260 uses PCIe 3.0 x8, while the GT 645M uses PCIe 3.0 x16.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon R7 M260 has an average benchmark score of 4499, while the NVIDIA GeForce GT 645M scores 4411. The difference is 88 points, roughly 2.0% in favor of AMD.

Q: Does the NVIDIA GeForce GT 645M win any benchmark test?

A: Yes, it wins the Geekbench Metal test with a score of 5679. The AMD Radeon R7 M260 has no Metal benchmark entry in the data, so this is an uncontested win for NVIDIA.

Q: How much faster is the AMD Radeon R7 M260 in OpenCL?

A: The AMD part scores 3708 versus 2680 for the NVIDIA part, a delta of 38.4%. This is the largest performance gap in any shared test.

Q: What is the memory bandwidth difference?

A: The GT 645M has a 128-bit memory bus providing 28.80 GB/s, while the R7 M260 has a 64-bit bus providing 14.40 GB/s. The NVIDIA part has exactly double the bandwidth.

Q: Which GPU has a higher boost clock?

A: The AMD Radeon R7 M260 boosts to 980 MHz, while the NVIDIA GeForce GT 645M boosts to 780 MHz. The AMD part runs 200 MHz higher at boost.

Q: Are both GPUs the same age?

A: No. The GT 645M was released on 2012-09-30, while the R7 M260 came later on 2014-06-10. NVIDIA’s part is nearly two years older.

Specification Differences

The table below highlights the fields where the two GPUs differ, excluding identical values like memory size (2 GB), memory type (DDR3), process node (28 nm), and foundry (TSMC).

| Specification | AMD Radeon R7 M260 | NVIDIA GeForce GT 645M |

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

| Architecture | GCN 3.0 | Kepler |

| Chip | Topaz | GK107 |

| Generation | Gem System (R7 M200) | GeForce 600M |

| Transistors | 1,550 million | 1,270 million |

| Die Size | 125 mm² | 118 mm² |

| Transistor Density | 12.4M / mm² | 10.8M / mm² |

| Base Clock | 940 MHz | 709 MHz |

| Boost Clock | 980 MHz | 780 MHz |

| Memory Bus Width | 64 bit | 128 bit |

| Memory Bandwidth | 14.40 GB/s | 28.80 GB/s |

| TMUs | 24 | 32 |

| ROPs | 8 | 16 |

| Pixel Rate | 7.840 GPixel/s | 6.240 GPixel/s |

| Texture Rate | 23.52 GTexel/s | 24.96 GTexel/s |

| FP32 | 752.6 GFLOPS | 599.0 GFLOPS |

| FP16 | 752.6 GFLOPS (1:1) | null |

| TDP | null | 32 W |

| Slot Width | null | IGP |

| Power Connectors | null | None |

| Bus Interface | PCIe 3.0 x8 | PCIe 3.0 x16 |

| Display Outputs | null | Portable Device Dependent |

| DirectX Support | 12 (12_0) | 12 (11_0) |

| Vulkan Support | 1.2.170 | 1.2.175 |

| Release Date | 2014-06-10 | 2012-09-30 |

| Predecessor | Solar System | GeForce 500M |

| Successor | Polaris Mobile | GeForce 700M |

Head-to-Head Benchmarks

The shared benchmark suite consists of two tests: Geekbench OpenCL and Geekbench Vulkan. The AMD Radeon R7 M260 wins both, but the margins differ substantially.

In OpenCL, the R7 M260 scores 3708 against the GT 645M’s 2680. The delta is 38.4%, meaning AMD’s part is more than a third faster. This is a large gap, likely driven by the R7 M260’s higher core clocks (940 MHz base vs 709 MHz base) and superior FP32 throughput of 752.6 GFLOPS versus 599.0 GFLOPS. The GT 645M’s wider memory bus does not compensate for the clock deficit in this compute-heavy workload.

In Vulkan, the R7 M260 wins again, but by a smaller margin: 5289 versus 4875, an 8.5% lead. The gap narrows here, suggesting that the GT 645M’s higher texture rate (24.96 GTexel/s vs 23.52 GTexel/s) and double the ROP count (16 vs 8) help it close the distance in graphics-oriented tasks, even though it still loses.

The GT 645M’s only benchmark win is in Geekbench Metal, where it scores 5679. Since the R7 M260 has no Metal entry, this test cannot be compared directly. However, the score is notably higher than either GPU’s OpenCL or Vulkan results, indicating that the NVIDIA part is well-optimized for Apple’s API. If a user’s workload is Metal-centric, the GT 645M’s data is more favorable.

The Verdict

From the data, the AMD Radeon R7 M260 is the better choice for general compute and cross-platform graphics performance. It wins both shared benchmarks, with a dominant 38.4% lead in OpenCL and a solid 8.5% lead in Vulkan. Its higher clocks, denser transistor layout, and newer architecture (GCN 3.0 vs Kepler) translate into measurable performance advantages. Users running OpenCL or Vulkan workloads should favor the AMD part without hesitation.

The NVIDIA GeForce GT 645M, however, is not without merit. Its Metal score of 5679 is the single highest benchmark result among all tests listed for either GPU, and it is the only GPU with any Metal data. For users in Apple ecosystems, this is the only viable choice between the two. Additionally, the GT 645M’s 32 W TDP is listed, while the R7 M260’s is absent, suggesting NVIDIA’s part may be easier to cool in thin laptops. The double memory bandwidth (28.80 GB/s vs 14.40 GB/s) and higher ROP count (16 vs 8) also give it an edge in bandwidth-sensitive scenarios.

The percentile rankings are identical at 26 for both GPUs, placing them in the same performance tier overall. The average benchmark scores are close (4499 vs 4411, a 2.0% gap), but the R7 M260’s wins are consistent across shared tests. The GT 645M’s case rests on Metal compatibility and power efficiency, not raw compute. Ultimately, the R7 M260 is the data-backed winner for most workloads, while the GT 645M is the specialist for Metal-centric systems.