AMD Radeon R5 M255 vs AMD Radeon R5 M330 Comparison

Head-to-Head Benchmarks

The recorded data shows a clear and consistent advantage for the AMD Radeon R5 M255 across both benchmark tests in the database. In the Geekbench OpenCL test, the R5 M255 scores 4650 against 4302 for the R5 M330, a lead of 8.1 percent. The Vulkan test shows an even wider gap: 4925 versus 4037, which translates to a 22 percent advantage for the M255. The M255 wins both head-to-head matchups; the M330 records zero wins.

Looking at the aggregate scores, the M255 averages 4788 across its benchmark entries, while the M330 averages 4170. That places the M255 in the 28th percentile of all GPUs in the database, against the 25th percentile for the M330. The nearest rivals for the M255 include the NVIDIA GeForce RTX 3080 12 GB at 4791 (a 0.1 percent delta against the M255, essentially a tie), the AMD Radeon R5 M335 at 4752 (0.8 percent behind), the NVIDIA GeForce 940MX at 4844 (1.2 percent ahead), and the AMD Radeon R8 M445DX at 4727 (1.3 percent behind). For the M330, the nearest rivals are the NVIDIA Quadro K2100M at 4151 (0.4 percent behind), the NVIDIA GeForce GTX 1050 Ti at 4193 (0.5 percent ahead), the NVIDIA Quadro K3000M at 4241 (1.7 percent ahead), and the AMD Radeon RX 9060 XT 8 GB at 4093 (1.9 percent behind).

The Vulkan delta of 22 percent is the largest single divergence between the two parts. In that workload, the M255 operates at a level that places it near the GeForce 940MX, while the M330 sits closer to the Quadro K2100M. The OpenCL gap of 8.1 percent is more moderate but still consistent with the M255's higher shading-unit count and wider memory bus.

Where Each One Wins

The M255 wins both recorded benchmark categories: OpenCL and Vulkan. No benchmark category in the database shows the M330 ahead. Therefore, the use-case split is straightforward. For any workload that leverages OpenCL compute, such as general-purpose GPU acceleration in productivity or media applications, the M255 provides the higher score. For Vulkan-based rendering, which is increasingly relevant in modern game engines and cross-platform graphics APIs, the M255's 22 percent advantage is decisive.

The M330 does hold a theoretical edge in raw pixel throughput. Its pixel rate is 8.240 GPixel/s versus 7.520 GPixel/s for the M255. That suggests the M330 could be marginally faster in fill-rate-bound scenarios, but the database benchmarks do not include a specific pixel-rate test, so no win is recorded there. The M330 also has a higher boost clock (1030 MHz versus 940 MHz), but that does not translate into any benchmark victory in the recorded data.

Architecture Differences

The two GPUs come from different generations of the same Gem System family. The M255 uses the Topaz chip built on GCN 3.0 architecture, while the M330 uses the Exo chip on GCN 1.0 architecture. This is a significant architectural split. GCN 3.0 is a later iteration with refinements over the original GCN design. The M255 is part of the Gem System (R5 M200) generation, while the M330 belongs to the Gem System (R5 M300) generation, meaning the M330 is nominally newer by generation numbering but uses an older architecture core.

Both parts are fabricated on a 28 nm process at TSMC, and both have the same transistor density (12.4 million transistors per mm² for the M255, 12.3 million for the M330). However, the transistor counts differ sharply: the M255 packs 1,550 million transistors on a 125 mm² die, while the M330 has 690 million transistors on a 56 mm² die. The M255 uses its larger die to house 384 shading units, 24 texture mapping units, and 8 ROPs. The M330 has 320 shading units, 20 TMUs, and 8 ROPs. So the M255 has 20 percent more shading units and 20 percent more TMUs, with equal ROP counts.

Compute rates reflect those core counts. The M255 delivers 721.9 GFLOPS of FP32 performance, while the M330 delivers 659.2 GFLOPS. The M255 also sustains a texture rate of 22.56 GTexel/s versus 20.60 GTexel/s for the M330. The M255 supports FP16 at the same 1:1 rate as FP32 (721.9 GFLOPS), while the M330 lists no FP16 capability in the database.

Specification Differences

| Specification | AMD Radeon R5 M255 | AMD Radeon R5 M330 |

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

| Chip | Topaz | Exo |

| Architecture | GCN 3.0 | GCN 1.0 |

| Generation | Gem System (R5 M200) | Gem System (R5 M300) |

| Transistors | 1,550 million | 690 million |

| Die size | 125 mm² | 56 mm² |

| Base clock | 925 MHz | 955 MHz |

| Boost clock | 940 MHz | 1030 MHz |

| Memory clock | 1000 MHz, 2 Gbps effective | 900 MHz, 1800 Mbps effective |

| Memory bus width | 128 bit | 64 bit |

| Memory bandwidth | 32.00 GB/s | 14.40 GB/s |

| Shading units | 384 | 320 |

| TMUs | 24 | 20 |

| Pixel rate | 7.520 GPixel/s | 8.240 GPixel/s |

| Texture rate | 22.56 GTexel/s | 20.60 GTexel/s |

| FP32 | 721.9 GFLOPS | 659.2 GFLOPS |

| FP16 | 721.9 GFLOPS (1:1) | Not listed |

| TDP | Not listed | 18 W |

| Slot width | Not listed | IGP |

| Power connectors | Not listed | None |

| Display outputs | Not listed | Portable Device Dependent |

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

| Release date | 2014-10-11 | 2015-05-04 |

The memory configuration is the most consequential difference. The M255 has a 128-bit bus with 32.00 GB/s bandwidth, more than double the M330's 64-bit bus at 14.40 GB/s. Both use 2 GB of DDR3, but the M255's wider bus gives it a substantial data throughput advantage. The M330 compensates with higher clocks (955 MHz base, 1030 MHz boost versus 925 MHz and 940 MHz), but the memory bandwidth gap is too large to overcome.

API support also differs at the DirectX level. The M255 supports DirectX 12 (12_0), while the M330 supports DirectX 12 (11_1). Both support OpenGL 4.6 and Vulkan 1.2.170. The M330 is the only one of the pair with a listed TDP of 18 W, and it is designated as an IGP with no power connectors, while the M255 leaves TDP and power connectors unlisted.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon R5 M255 has an average score of 4788, compared to 4170 for the AMD Radeon R5 M330.

Q: How large is the Vulkan performance gap?

A: The M255 scores 4925 in the Geekbench Vulkan test, while the M330 scores 4037. That is a 22 percent advantage for the M255.

Q: Do both GPUs have the same memory bus width?

A: No. The M255 has a 128-bit bus, while the M330 has a 64-bit bus. Memory bandwidth is 32.00 GB/s for the M255 and 14.40 GB/s for the M330.

Q: Which GPU has more shading units?

A: The M255 has 384 shading units. The M330 has 320 shading units, which is 20 percent fewer.

Q: Does the M330 have any advantage in the benchmark data?

A: No. The M330 wins zero head-to-head benchmark tests. It does have a higher pixel rate (8.240 GPixel/s versus 7.520 GPixel/s) and a higher boost clock (1030 MHz versus 940 MHz), but neither translates into a recorded benchmark win.

Q: What are the direct rivals for each GPU according to the database?

A: For the M255, the nearest rivals are the NVIDIA GeForce RTX 3080 12 GB, AMD Radeon R5 M335, NVIDIA GeForce 940MX, and AMD Radeon R8 M445DX. For the M330, the nearest rivals are the NVIDIA Quadro K2100M, NVIDIA GeForce GTX 1050 Ti, NVIDIA Quadro K3000M, and AMD Radeon RX 9060 XT 8 GB.

The Verdict

The data points to a single recommendation: the AMD Radeon R5 M255 is the stronger GPU in this pairing. It wins both benchmark tests, holds an 8.1 percent OpenCL lead and a 22 percent Vulkan lead, and carries a higher average score (4788 versus 4170). Its memory subsystem is decisively better, with a 128-bit bus and 32.00 GB/s bandwidth against the M330's 64-bit bus and 14.40 GB/s. The M255 also has more shading units (384 versus 320), more TMUs (24 versus 20), and higher FP32 throughput (721.9 GFLOPS versus 659.2 GFLOPS).

The M330 is not without merit. It has a higher base and boost clock, a higher pixel rate, and a lower transistor count (690 million versus 1,550 million), which may imply lower power draw, and it is the only one of the two with a listed 18 W TDP. It also carries a newer generation label (R5 M300 versus R5 M200) and a later release date. But none of those factors appear in the benchmark results. The M330's DirectX 12 support is limited to 11_1, while the M255 supports 12_0, and the M330 lacks any listed FP16 capability.

Users choosing between these two mobile GPUs should prioritize the M255 if compute performance, memory bandwidth, or graphics API coverage matters. The M330 only makes sense if the 18 W TDP and IGP form factor are the deciding constraints, since the database records no performance category where the M330 comes out ahead. The M255 sits in a higher performance percentile (28th versus 25th) and matches or beats several adjacent rivals, including the Radeon R5 M335 and Radeon R8 M445DX, while keeping pace with the GeForce 940MX within 1.2 percent. For the M330, the nearest comparable is the Quadro K2100M, a professional mobile GPU from an older generation, which the M330 trails by 0.4 percent. The verdict is clear: the M255 is the superior part in every measured benchmark category.