AMD Radeon R5 M255 vs AMD Radeon R7 M445 Comparison

The AMD Radeon R7 M445 and the AMD Radeon R5 M255 are both mobile graphics solutions from the same manufacturer, built on the same architecture, and share several core specifications. However, the recorded benchmarks show a clear performance gap between them. The R7 M445 records an average benchmark score of 5358, placing it in the 31st percentile of all GPUs in the database. The R5 M255, by contrast, averages 4788, which puts it in the 28th percentile. This data indicates that the R7 M445 is the stronger performer, and the head-to-head results confirm this.

Head-to-Head Benchmarks

The database contains one direct benchmark comparison between these two GPUs: the Geekbench OpenCL test. In this test, the R7 M445 scores 5358, while the R5 M255 scores 4650. The R7 M445 wins this test by a margin of 15.2 percent. This is the only head-to-head metric recorded, and it establishes the R7 M445 as the decisive winner in this matchup.

Looking at the broader context, the R7 M445’s 5358 OpenCL score is remarkably close to several other GPUs in the database. It sits just 0.2 percent behind the Intel UHD Graphics P630, which scores 5370. It also edges out the NVIDIA GeForce 840M (5322) by 0.7 percent and the NVIDIA GeForce 930A (5317) by 0.8 percent. Perhaps most surprisingly, the R7 M445 is only 0.9 percent ahead of the NVIDIA GeForce GTX 980M, which scores 5308. These small deltas show that the R7 M445 occupies a competitive position among a wide range of discrete and integrated solutions, despite its modest overall percentile ranking.

The R5 M255’s OpenCL score of 4650 places it in a different tier. It trails the NVIDIA GeForce RTX 3080 12 GB (4791) by 0.1 percent, which is a negligible difference in practical terms. It is also 0.8 percent ahead of the AMD Radeon R5 M335 (4752) and 1.3 percent ahead of the AMD Radeon R8 M445DX (4727). However, it lags behind the NVIDIA GeForce 940MX (4844) by 1.2 percent. The R5 M255’s scores, while lower than the R7 M445’s, still show it competing with a set of GPUs that are generally considered entry-level or mid-range mobile parts.

The 15.2 percent delta between the two AMD parts is substantial when viewed against these rival comparisons. For instance, the difference between the R7 M445 and the R5 M255 is far larger than the differences between the R7 M445 and any of its nearest rivals. The data shows that the R7 M445 does not just edge out the R5 M255, it outperforms it by a wide margin in the OpenCL workload.

The Verdict

From the recorded data, the AMD Radeon R7 M445 is the clear choice for users who prioritize raw compute performance. Its OpenCL score of 5358 is 15.2 percent higher than the R5 M255’s 4650, and its average benchmark score of 5358 versus 4788 reinforces this lead. The R7 M445 also holds a higher overall percentile ranking at 31 compared to the R5 M255’s 28, meaning it outperforms a larger fraction of the GPUs in the database.

The R5 M255, however, is not without its own merits. It has a higher base clock and a higher boost clock than the R7 M445, and it includes more shading units and texture mapping units. These specifications suggest that the R5 M255 may have a different performance profile in certain workloads, though the benchmark data does not support this in the OpenCL test. The R5 M255 also records an additional Vulkan score of 4925, which the R7 M445 does not have in the database. This Vulkan result is higher than its OpenCL score, indicating that the R5 M255 may perform better in APIs that leverage asynchronous compute or other modern features.

For a user choosing between these two based on the database alone, the R7 M445 is the safer bet for general compute tasks and applications that rely on OpenCL. The R5 M255 could be considered if the software in question uses Vulkan, as its recorded Vulkan score is respectable, but the lack of a comparable Vulkan score for the R7 M445 makes a direct comparison in that API impossible. The data shows that the R7 M445 wins the only direct comparison, and it has a higher average score across all recorded benchmarks.

Architecture Differences

Both GPUs are built on the same GCN 3.0 architecture and use the same 28 nm process node from TSMC. They share the same transistor count of 1,550 million and the same die size of 125 mm², which translates to a transistor density of 12.4 million transistors per square millimeter. This means that the fundamental building blocks of both chips are identical, and any performance differences must come from other specification variations.

The R7 M445 uses the Meso chip, while the R5 M255 uses the Topaz chip. Despite the different chip names, both are manufactured on the same process and have the same dimensions. The architecture generation is listed as "Gem System" for both, with the R7 M445 belonging to the R7 M400 generation and the R5 M255 belonging to the R5 M200 generation. This generational difference is notable because the R7 M445 was released later, on 2016-05-14, while the R5 M255 came out earlier, on 2014-10-11.

Both GPUs support DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.2.170. They also both use a PCIe 3.0 x8 bus interface. The predecessor and successor fields are identical for both: they both succeed the Solar System generation and are succeeded by Polaris Mobile. This indicates that they occupy similar positions in the product lineage, with the R7 M445 being a later refinement within the same architectural family.

The memory subsystems differ significantly between the two. The R7 M445 uses 4 GB of GDDR5 memory with a 64-bit bus width, while the R5 M255 uses 2 GB of DDR3 memory with a 128-bit bus width. Interestingly, both achieve the same memory bandwidth of 32.00 GB/s, because the R7 M445’s faster GDDR5 memory operates at 4 Gbps effective, while the R5 M255’s DDR3 operates at 2 Gbps effective. The R7 M445’s memory clock is listed as 1000 MHz with 4 Gbps effective, while the R5 M255’s memory clock is 1000 MHz with 2 Gbps effective.

Specification Differences

The two GPUs diverge on several key specifications. The R7 M445 has a base clock of 780 MHz and a boost clock of 920 MHz, while the R5 M255 runs higher at 925 MHz base and 940 MHz boost. This gives the R5 M255 a higher operating frequency for the core, which can be beneficial in clock-sensitive workloads.

The shading units differ: the R7 M445 has 320, while the R5 M255 has 384. This advantage in shading units for the R5 M255 is significant, as it provides more parallel compute lanes. Similarly, the texture mapping units are 20 for the R7 M445 and 24 for the R5 M255. Both have 8 render output units, so the pixel processing capability is similar.

The calculated rates reflect these differences. The R7 M445 achieves a pixel rate of 7.360 GPixel/s and a texture rate of 18.40 GTexel/s. The R5 M255 achieves a slightly higher pixel rate of 7.520 GPixel/s and a texture rate of 22.56 GTexel/s. The floating-point performance also favors the R5 M255: it delivers 721.9 GFLOPS for both FP32 and FP16 (with a 1:1 ratio), while the R7 M445 delivers 588.8 GFLOPS for both FP32 and FP16. This means the R5 M255 has roughly 22.6 percent more raw FP32 compute potential on paper, yet it loses the OpenCL benchmark by 15.2 percent. This discrepancy suggests that memory bandwidth or memory latency may be the limiting factor for the R5 M255, or that the benchmark workload favors the R7 M445’s memory configuration.

The memory size differs as well, with the R7 M445 offering 4 GB versus the R5 M255’s 2 GB. The memory type is also different, GDDR5 for the R7 M445 and DDR3 for the R5 M255, though the effective bus widths and bandwidths result in the same 32.00 GB/s throughput. The R7 M445 is listed as an IGP (integrated graphics processor) with portable device dependent display outputs, while the R5 M255 has no slot width or display output information recorded.

FAQ

Q: Which GPU has a higher average benchmark score?

A: The AMD Radeon R7 M445 has an average benchmark score of 5358, while the AMD Radeon R5 M255 has an average score of 4788. The R7 M445 also holds a higher percentile rank at 31 versus 28.

Q: What is the result of the direct OpenCL benchmark comparison?

A: In the Geekbench OpenCL test, the R7 M445 scores 5358 and the R5 M255 scores 4650. The R7 M445 wins this test by 15.2 percent.

Q: How does the R5 M255 compare to the NVIDIA GeForce 940MX?

A: The R5 M255 scores 4650 in OpenCL, while the NVIDIA GeForce 940MX scores 4844, making the R5 M255 1.2 percent slower than the 940MX.

Q: Do both GPUs use the same memory bandwidth?

A: Yes, both achieve a memory bandwidth of 32.00 GB/s, but the R7 M445 uses 4 GB of GDDR5 on a 64-bit bus with 4 Gbps effective, while the R5 M255 uses 2 GB of DDR3 on a 128-bit bus with 2 Gbps effective.

Q: Which GPU has more shading units?

A: The AMD Radeon R5 M255 has 384 shading units, while the AMD Radeon R7 M445 has 320 shading units. The R5 M255 also has 24 texture mapping units versus 20 on the R7 M445.

Q: What is the release date difference between the two?

A: The R7 M445 was released on 2016-05-14, while the R5 M255 was released on 2014-10-11. Both are now end-of-life products.

Where Each One Wins

The AMD Radeon R7 M445 wins in the recorded OpenCL benchmark, scoring 5358 against the R5 M255’s 4650, a 15.2 percent advantage. This makes it the stronger choice for applications that rely on OpenCL compute, such as certain rendering tasks, physics simulations, or general-purpose GPU computing. Its higher average benchmark score and better percentile ranking also indicate that it performs more consistently across the database’s recorded metrics.

The R7 M445 also offers twice the memory capacity (4 GB versus 2 GB) and uses faster GDDR5 memory, which can be an advantage in workloads that require large datasets or high memory throughput, even though the aggregate bandwidth is identical. For users who need more video memory for textures or compute buffers, the R7 M445 is the better option.

The AMD Radeon R5 M255, despite losing the OpenCL test, has its own strengths. It has a higher base clock (925 MHz versus 780 MHz) and boost clock (940 MHz versus 920 MHz), which can improve performance in clock-bound scenarios. It also has more shading units (384 versus 320) and more texture mapping units (24 versus 20), leading to higher theoretical pixel and texture rates: 7.520 GPixel/s versus 7.360 GPixel/s, and 22.56 GTexel/s versus 18.40 GTexel/s, respectively. Its FP32 compute is also higher at 721.9 GFLOPS versus 588.8 GFLOPS.

The R5 M255 also has a recorded Vulkan score of 4925, which is higher than its OpenCL score. This suggests that the R5 M255 may be more capable in Vulkan-based applications, though the R7 M445 has no recorded Vulkan score for comparison. The R5 M255’s wider 128-bit memory bus may also help in specific access patterns, despite the same effective bandwidth.

In summary, the R7 M445 wins on actual benchmark results and memory capacity, while the R5 M255 wins on theoretical compute specifications and clock speeds. For a user relying on the database’s measured performance, the R7 M445 is the recommended pick. For a user who values higher clock rates and more shading units, the R5 M255 presents a plausible alternative, but the data does not show it outperforming the R7 M445 in any recorded direct comparison.