AMD Radeon R6 M255DX vs AMD Radeon R7 M260X Comparison

FAQ

Q: Which GPU delivers the higher average benchmark score?

A: The AMD Radeon R7 M260X holds the higher average, with an avgBenchmarkScore of 5161 versus 4867 for the AMD Radeon R6 M255DX. This places the R7 M260X at the 30th percentile of all GPUs, while the R6 M255DX sits at the 28th percentile.

Q: How do the two compare in the Geekbench Vulkan test?

A: The Radeon R6 M255DX wins the head-to-head Geekbench Vulkan test, scoring 4867 against the R7 M260X's 4631. That is a 4.8% advantage for the R6 M255DX in this specific API workload.

Q: What is the memory configuration difference between the two?

A: The R7 M260X uses dedicated 1024 MB of GDDR5 memory on a 128-bit bus, yielding 64.00 GB/s of bandwidth. The R6 M255DX, in contrast, uses System Shared memory with a bus width and bandwidth that are both System Dependent.

Q: Are these GPUs built on the same manufacturing process?

A: Yes, both are fabricated by TSMC on a 28 nm process node. They also share the same transistor density of 12.3M / mm², though the R7 M260X has a larger die at 77 mm² compared to the R6 M255DX's 56 mm².

Q: Which GPU has higher clock speeds?

A: The R6 M255DX runs at a base clock of 780 MHz and a boost clock of 855 MHz. The R7 M260X is lower in both respects, with a 620 MHz base and a 715 MHz boost.

Q: What is the production status of these two mobile GPUs?

A: Both are listed as End-of-life. The R7 M260X was released on 2015-12-05, while the R6 M255DX came earlier, on 2014-01-06.

Architecture Differences

Both GPUs are built on AMD's GCN 1.0 architecture, but they are distinct chips with different configurations. The R7 M260X uses the Opal chip, belonging to the "Gem System (R7 M200)" generation, while the R6 M255DX uses the Jet chip from the "Gem System Hybrid (Rx M200)" lineage. This hybrid designation hints at the R6 M255DX's fundamental reliance on shared system resources.

The transistor counts diverge significantly. The R7 M260X packs 950 million transistors on a 77 mm² die, whereas the R6 M255DX contains 690 million transistors on a smaller 56 mm² die. Both are produced by TSMC at 28 nm with identical transistor density of 12.3M / mm², but the R7 M260X's larger physical footprint accommodates more compute units.

The execution resources favor the R7 M260X. It features 384 shading units, 24 texture mapping units, and 8 ROPs. The R6 M255DX steps down to 320 shading units and 20 TMUs, though it retains the same 8 ROPs. This means the R7 M260X has a 20% advantage in both shader count and texture unit count.

Clock speeds tell a different story. The R6 M255DX runs at 780 MHz base and 855 MHz boost, substantially higher than the R7 M260X's 620 MHz base and 715 MHz boost. This clock advantage partially compensates for the R6 M255DX's fewer execution units.

Memory architecture represents the most significant structural difference. The R7 M260X uses dedicated 1024 MB of GDDR5 memory on a 128-bit bus, delivering 64.00 GB/s of bandwidth. The R6 M255DX relies entirely on System Shared memory, with its bandwidth marked as System Dependent. The R7 M260X also has its own memory clock of 1000 MHz (4 Gbps effective), while the R6 M255DX's memory clock is tied to the system.

The bus interfaces reflect their different positions. The R7 M260X connects via PCIe 3.0 x8, while the R6 M255DX is an IGP (integrated graphics processor) with no discrete bus interface. Power connector requirements also differ: the R7 M260X lists "None," and the R6 M255DX has no power connector data, consistent with its integrated design. Both GPUs support the same API levels: DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.170.

Head-to-Head Benchmarks

The single direct comparison available in the data is the Geekbench Vulkan test. Here, the Radeon R6 M255DX emerges victorious with a score of 4867, beating the R7 M260X's 4631 by a margin of 4.8%. This is a notable result because the R7 M260X has the higher average benchmark score overall, yet loses in this specific API test.

The Vulkan result likely reflects the R6 M255DX's higher clock speeds. Its 855 MHz boost clock versus the R7 M260X's 715 MHz boost represents a roughly 19.6% clock advantage. Even with 64 fewer shading units, the R6 M255DX manages to overcome the deficit in this workload, suggesting Vulkan's lower overhead favors the faster-clocked chip.

However, the broader benchmark picture favors the R7 M260X. Its avgBenchmarkScore of 5161 includes both the Geekbench OpenCL score of 5690 and the Geekbench Vulkan score of 4631. The R6 M255DX has only a single recorded benchmark, the Geekbench Vulkan score of 4867, which doubles as its average. The R7 M260X's OpenCL result is particularly strong, exceeding its own Vulkan score by 1059 points, and it drives the overall average 294 points higher than the R6 M255DX's figure.

In terms of theoretical throughput, the two GPUs are remarkably close. The R7 M260X posts 549.1 GFLOPS of FP32 performance, while the R6 M255DX achieves 547.2 GFLOPS — a difference of only 1.9 GFLOPS, or about 0.3%. Texture rates are similarly matched: 17.16 GTexel/s for the R7 M260X versus 17.10 GTexel/s for the R6 M255DX. The R6 M255DX actually leads in pixel rate, however, at 6.840 GPixel/s compared to the R7 M260X's 5.720 GPixel/s, a 19.6% advantage that mirrors its boost clock lead.

The nearest rival data places each GPU in context. The R7 M260X sits just 0.1% above the NVIDIA Quadro K3100M (5154) and 1% below the NVIDIA Quadro 4000M (5211). It also trails the NVIDIA GeForce GTX 760M (5236) by 1.4% while leading the AMD Radeon R7 240 (5063) by 1.9%. The R6 M255DX, meanwhile, is 0.2% ahead of the NVIDIA GeForce GTX 560M (4855) and 0.5% ahead of the NVIDIA GeForce 940MX (4844). It falls 0.5% short of the NVIDIA GeForce GTS 450 (4893) and 0.7% behind the NVIDIA GeForce RTX 5060 Ti 8 GB (4901). The presence of a modern RTX card in the R6 M255DX's rival list underscores how narrow the performance band is around its score.

The Verdict

The benchmark data paints a nuanced picture. The Radeon R7 M260X is the stronger overall GPU, with an average benchmark score of 5161 that places it in the 30th percentile of all GPUs. The Radeon R6 M255DX trails with 4867 and sits in the 28th percentile. For general compute workloads, particularly OpenCL, the R7 M260X is the clear choice — its 5690 OpenCL score demonstrates a substantial capability that the R6 M255DX cannot match, since no OpenCL result exists for it.

Yet the R6 M255DX has a legitimate claim in Vulkan-specific applications. Its 4867 Vulkan score beats the R7 M260X's 4631 by 4.8%, meaning users who prioritize Vulkan-based games or workloads would see better performance from the R6 M255DX despite its lower overall average.

Architecturally, the R7 M260X offers more execution resources: 384 shading units and 24 TMUs versus 320 and 20, respectively. It also brings dedicated GDDR5 memory with 64.00 GB/s of bandwidth, which eliminates the performance variability inherent in the R6 M255DX's System Shared memory configuration. The R7 M260X's PCIe 3.0 x8 interface further distinguishes it from the R6 M255DX's IGP bus connection.

The R6 M255DX counters with higher clocks (855 MHz boost vs. 715 MHz) and a superior pixel rate (6.840 GPixel/s vs. 5.720 GPixel/s). Its integrated nature means it requires no power connectors and likely fits in thinner chassis designs, though the data does not specify TDP or slot width for the R7 M260X.

For laptop buyers choosing between these two, the decision hinges on workload. The R7 M260X is the safer pick for mixed usage and compute-heavy tasks, offering a higher average score and dedicated memory. The R6 M255DX is preferable for Vulkan-centric scenarios where its 4.8% lead in that API matters more than the overall average. Given that the R7 M260X wins the average benchmark comparison by 294 points (about 6%) while losing only one specific test, the data favors the R7 M260X for most users. The R6 M255DX's single Vulkan win, while real, does not outweigh the R7 M260X's broader benchmark superiority.

Specification Differences

| Specification | AMD Radeon R7 M260X | AMD Radeon R6 M255DX |

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

| Chip | Opal | Jet |

| Generation | Gem System (R7 M200) | Gem System Hybrid (Rx M200) |

| Transistors | 950 million | 690 million |

| Die Size | 77 mm² | 56 mm² |

| Base Clock | 620 MHz | 780 MHz |

| Boost Clock | 715 MHz | 855 MHz |

| Memory | 1024 MB GDDR5 | System Shared |

| Memory Bus | 128 bit | System Shared |

| Bandwidth | 64.00 GB/s | System Dependent |

| Memory Clock | 1000 MHz (4 Gbps effective) | System Shared |

| Shading Units | 384 | 320 |

| TMUs | 24 | 20 |

| ROPs | 8 | 8 |

| Pixel Rate | 5.720 GPixel/s | 6.840 GPixel/s |

| Texture Rate | 17.16 GTexel/s | 17.10 GTexel/s |

| FP32 | 549.1 GFLOPS | 547.2 GFLOPS |

| Bus Interface | PCIe 3.0 x8 | IGP |

| Slot Width | Not specified | IGP |

| Power Connectors | None | Not specified |

| Release Date | 2015-12-05 | 2014-01-06 |

The two GPUs share identical process nodes, transistor density, foundry, architecture, ROP count, and API support. All other specifications in the comparison table above show differences, with the most consequential being memory configuration, execution unit counts, and clock speeds.