AMD Radeon R6 M255DX vs AMD Radeon R7 M445 Comparison

Head-to-Head Benchmarks

The recorded benchmark data does not include any shared test where both AMD Radeon R7 M445 and AMD Radeon R6 M255DX produced directly comparable scores. The database contains a Geekbench OpenCL result for the R7 M445 and a Geekbench Vulkan result for the R6 M255DX, which are different API workloads and therefore cannot be placed side by side as a like-for-like comparison. The head-to-head benchmark table is empty, and neither part scores a formal win against the other.

What the separate measurements do show is how each GPU positions itself within its own performance neighborhood. The R7 M445 records an average Geekbench OpenCL score of 5358, which places it at the 31st percentile among all GPUs in the database. Its closest rivals are tightly clustered around that figure. The Intel UHD Graphics P630 averages 5370, a margin of 0.2 percent above the R7 M445. The NVIDIA GeForce 840M scores 5322, which is 0.7 percent lower, and the NVIDIA GeForce 930A averages 5317, 0.8 percent behind. Even the NVIDIA GeForce GTX 980M, a far higher-tier part in most respects, appears in the nearest-rival list with an average score of 5308, only 0.9 percent below the R7 M445 in this particular OpenCL measurement. The practical takeaway is that the R7 M445 sits in a very dense performance band where a few points of benchmark score separate it from several otherwise very different GPUs.

The R6 M255DX, by contrast, is measured through Geekbench Vulkan with an average score of 4867, placing it at the 28th percentile across all GPUs. Its nearest rivals again bracket the score closely. The NVIDIA GeForce GTS 450 averages 4893, which is 0.5 percent above the R6 M255DX. The NVIDIA GeForce RTX 5060 Ti 8 GB, a modern discrete card, averages 4901, 0.7 percent higher. On the lower side, the NVIDIA GeForce GTX 560M averages 4855, 0.2 percent below, and the NVIDIA GeForce 940MX averages 4844, 0.5 percent below. The spread here is even tighter than for the R7 M445, with all four rivals falling within less than one percentage point of the R6 M255DX score.

Because the two benchmark runs use different API paths, the data does not support a direct statement that one GPU outperforms the other. The R7 M445's OpenCL score of 5358 is numerically higher than the R6 M255DX's Vulkan score of 4867, but that gap reflects workload differences as much as hardware capability. The percentile ranking puts the R7 M445 at 31 percent versus 28 percent for the R6 M255DX, a modest separation in overall standing. The only defensible conclusion from the recorded numbers is that both GPUs occupy the lower-middle range of the performance distribution, with the R7 M445 holding a slight edge in percentile position and raw score magnitude, though not in a directly comparable test.

Architecture Differences

The two GPUs come from different generations of AMD's Graphics Core Next design. The R7 M445 is built on GCN 3.0, while the R6 M255DX uses the original GCN 1.0 architecture. This generation gap shows up in several measurable ways beyond the architecture label itself.

The process nodes are identical at 28 nm and both are fabricated by TSMC, but the underlying chips differ sharply in scale. The R7 M445 uses the Meso chip, which packs 1,550 million transistors into a die size of 125 mm². That works out to a transistor density of 12.4 million transistors per square millimeter. The R6 M255DX uses the Jet chip, containing 690 million transistors on a 56 mm² die, for a density of 12.3 million per square millimeter. The transistor counts and die areas are very different, yet the density figures are almost the same, which reflects the similar 28 nm manufacturing process rather than any architectural efficiency difference.

Core counts are identical. Both GPUs have 320 shading units, 20 texture mapping units, and 8 render output units. The compute configuration is therefore the same on paper, but clock speeds and memory behavior separate them. The R7 M445 runs at a base clock of 780 MHz and boosts to 920 MHz. The R6 M255DX also starts at 780 MHz but boosts only to 855 MHz. The higher boost clock on the R7 M445 contributes to its higher pixel rate of 7.360 GPixel/s versus 6.840 GPixel/s for the R6 M255DX, and a texture rate of 18.40 GTexel/s versus 17.10 GTexel/s. Floating point performance follows the same pattern: the R7 M445 delivers 588.8 GFLOPS in FP32, while the R6 M255DX delivers 547.2 GFLOPS. The R7 M445 also lists FP16 performance at 588.8 GFLOPS with a 1:1 ratio, whereas the R6 M255DX has no recorded FP16 figure.

Memory is the largest architectural divergence. The R7 M445 has dedicated 4 GB of GDDR5 memory on a 64-bit bus, yielding 32.00 GB/s of bandwidth, with a memory clock of 1000 MHz and 4 Gbps effective data rate. The R6 M255DX has no dedicated memory at all: its memory size, type, and bus width are all listed as "System Shared," with bandwidth described as "System Dependent." This means the R6 M255DX relies entirely on shared system memory, which introduces latency and bandwidth constraints that a dedicated GDDR5 implementation avoids. The R7 M445's 32.00 GB/s of dedicated bandwidth is a clear structural advantage, even if the 64-bit bus is narrow by discrete GPU standards.

API support also differs. The R7 M445 supports DirectX 12 at feature level 12_0, while the R6 M255DX supports DirectX 12 at the lower feature level 11_1. Both support OpenGL 4.6 and Vulkan 1.2.170. The generation labels reflect this split: the R7 M445 belongs to the Gem System (R7 M400) generation, while the R6 M255DX is from the Gem System Hybrid (Rx M200) generation. The bus interface also differs, with the R7 M445 using PCIe 3.0 x8 and the R6 M255DX listed simply as IGP.

FAQ

Q: Which GPU has a higher boost clock?

A: The AMD Radeon R7 M445 boosts to 920 MHz, while the AMD Radeon R6 M255DX boosts to 855 MHz. Both have a base clock of 780 MHz.

Q: Do these GPUs have the same number of shading units?

A: Yes, both the R7 M445 and the R6 M255DX have 320 shading units, along with 20 texture mapping units and 8 render output units.

Q: What is the memory configuration difference?

A: The R7 M445 uses 4 GB of dedicated GDDR5 memory on a 64-bit bus with 32.00 GB/s bandwidth. The R6 M255DX uses system shared memory with system dependent bandwidth, meaning it has no dedicated video memory.

Q: How do their benchmark scores compare?

A: The R7 M445 records a Geekbench OpenCL score of 5358 at the 31st percentile, while the R6 M255DX records a Geekbench Vulkan score of 4867 at the 28th percentile. These are different API tests, so they are not directly comparable.

Q: Which GPU has a higher transistor count?

A: The R7 M445 has 1,550 million transistors on a 125 mm² die, while the R6 M255DX has 690 million transistors on a 56 mm² die.

Q: What DirectX feature levels do they support?

A: The R7 M445 supports DirectX 12 at feature level 12_0, while the R6 M255DX supports DirectX 12 at feature level 11_1. Both support OpenGL 4.6 and Vulkan 1.2.170.

Specification Differences

The following fields differ between the two GPUs in the database records:

• Architecture: GCN 3.0 for the R7 M445, GCN 1.0 for the R6 M255DX
• Chip: Meso for the R7 M445, Jet for the R6 M255DX
• Generation: Gem System (R7 M400) for the R7 M445, Gem System Hybrid (Rx M200) for the R6 M255DX
• Transistors: 1,550 million for the R7 M445, 690 million for the R6 M255DX
• Die Size: 125 mm² for the R7 M445, 56 mm² for the R6 M255DX
• Transistor Density: 12.4M / mm² for the R7 M445, 12.3M / mm² for the R6 M255DX
• Boost Clock: 920 MHz for the R7 M445, 855 MHz for the R6 M255DX
• Memory Clock: 1000 MHz with 4 Gbps effective for the R7 M445, System Shared for the R6 M255DX
• Memory Size: 4 GB for the R7 M445, System Shared for the R6 M255DX
• Memory Type: GDDR5 for the R7 M445, System Shared for the R6 M255DX
• Memory Bus Width: 64 bit for the R7 M445, System Shared for the R6 M255DX
• Memory Bandwidth: 32.00 GB/s for the R7 M445, System Dependent for the R6 M255DX
• Pixel Rate: 7.360 GPixel/s for the R7 M445, 6.840 GPixel/s for the R6 M255DX
• Texture Rate: 18.40 GTexel/s for the R7 M445, 17.10 GTexel/s for the R6 M255DX
• FP32 Performance: 588.8 GFLOPS for the R7 M445, 547.2 GFLOPS for the R6 M255DX
• FP16 Performance: 588.8 GFLOPS (1:1) for the R7 M445, not recorded for the R6 M255DX
• DirectX Support: 12 (12_0) for the R7 M445, 12 (11_1) for the R6 M255DX
• Bus Interface: PCIe 3.0 x8 for the R7 M445, IGP for the R6 M255DX
• Release Date: 2016-05-14 for the R7 M445, 2014-01-06 for the R6 M255DX
• Predecessor: Solar System for the R7 M445, not recorded for the R6 M255DX
• Successor: Polaris Mobile for the R7 M445, not recorded for the R6 M255DX
• Benchmark Test: Geekbench OpenCL for the R7 M445, Geekbench Vulkan for the R6 M255DX
• Average Benchmark Score: 5358 for the R7 M445, 4867 for the R6 M255DX
• Percentile vs All GPUs: 31 for the R7 M445, 28 for the R6 M255DX

Fields that are the same include the 28 nm process node, TSMC foundry, base clock of 780 MHz, 320 shading units, 20 TMUs, 8 ROPs, IGP slot width, portable device dependent display outputs, OpenGL 4.6 and Vulkan 1.2.170 support, end-of-life production status, and no recorded TDP or launch MSRP.

Where Each One Wins

The R7 M445 wins on raw architectural features. Its dedicated 4 GB of GDDR5 memory with 32.00 GB/s bandwidth is a substantial advantage over the R6 M255DX's system shared memory, which has system dependent bandwidth and no dedicated allocation. For workloads that stress memory throughput, such as texture-heavy rendering or higher resolution framebuffers, the R7 M445 has a structural edge that the R6 M255DX cannot offset through any other specification. The R7 M445 also holds higher clock rates, with a boost of 920 MHz versus 855 MHz, and that translates into higher pixel rate, texture rate, and FP32 throughput. The 588.8 GFLOPS of FP32 compute on the R7 M445 versus 547.2 GFLOPS on the R6 M255DX is a roughly 7.6 percent gap in raw math throughput, which matters for compute-oriented tasks. The newer GCN 3.0 architecture and DirectX 12 feature level 12_0 support also give it a more modern feature set, and the PCIe 3.0 x8 bus interface allows for more flexible integration than a plain IGP connection.

The R6 M255DX wins on the basis of its benchmark showing relative to its nearest rivals. Its Geekbench Vulkan score of 4867 places it within 0.7 percent of the NVIDIA GeForce RTX 5060 Ti 8 GB, a modern discrete GPU, and within 0.5 percent of the NVIDIA GeForce GTS 450. The recorded data shows the R6 M255DX outperforming the NVIDIA GeForce GTX 560M by 0.2 percent and the NVIDIA GeForce 940MX by 0.5 percent. This tight clustering against a broad range of rivals, including much more expensive discrete parts, indicates that the R6 M255DX's shared memory architecture does not severely handicap it in the specific Vulkan workload measured. For users constrained to a system with no dedicated VRAM, the R6 M255DX demonstrates that it can still deliver competitive results in that test.

In practical use-case terms, the R7 M445 is the better choice for scenarios where dedicated memory bandwidth is critical, such as gaming at higher resolutions or running applications that allocate large textures. The R6 M255DX, with its system shared memory, is more suited to lightweight tasks where the system memory subsystem can keep up, and its Vulkan benchmark score suggests it handles modern API workloads reasonably well. The R7 M445's higher pixel rate and texture rate give it an advantage in fill-rate-bound scenes, while the R6 M255DX's lower power footprint, implied by its smaller die and transistor count, could favor thermally constrained designs. Neither GPU is positioned for high-end performance, as both sit below the 31st percentile in the database, but the R7 M445 offers the more complete hardware package for applications that can exploit dedicated memory and higher clocks.