AMD Radeon R5 M255 vs AMD Radeon R7 Graphics Comparison

AMD Radeon R7 Graphics and AMD Radeon R5 M255 are two end-of-life mobile graphics solutions from AMD that, despite sharing the same underlying compute architecture family, deliver distinctly different performance profiles depending on the workload. The data shows a split decision: the integrated R7 Graphics wins decisively in Vulkan compute, while the discrete R5 M255 takes the lead in OpenCL. With average benchmark scores of 4998 for the R7 and 4788 for the R5, the two are separated by roughly 4.4%, yet their individual strengths and architectural differences paint a more nuanced picture for database readers tracking legacy mobile GPUs.

Where Each One Wins

The benchmark results indicate a clear division of labor between these two parts. The AMD Radeon R7 Graphics, an integrated graphics processor (IGP) built into Kaveri APUs, dominates in the Geekbench Vulkan test. It scores 5980 points, which is 21.4% higher than the R5 M255’s 4925 in the same test. This is a substantial margin, suggesting that the R7’s architecture and driver stack are particularly well-optimized for Vulkan’s compute and graphics workloads. For any application leveraging Vulkan—whether modern game engines or compute APIs—the R7 Graphics is the stronger choice according to the data.

Conversely, the AMD Radeon R5 M255, a discrete mobile GPU based on the Topaz chip, wins the Geekbench OpenCL test. It scores 4650 points versus the R7’s 4015, a delta of 13.7% in favor of the discrete part. OpenCL remains a common compute standard for legacy applications, video encoding, and scientific workloads, so the R5 M255 holds an edge in scenarios that rely on this API. The R5 M255 also benefits from dedicated memory: it has 2 GB of DDR3 on a 128-bit bus, yielding 32.00 GB/s of bandwidth, whereas the R7 relies on system-shared memory with bandwidth described as “System Dependent.” This dedicated memory arrangement likely contributes to the R5’s OpenCL advantage, as it avoids contention with the CPU for memory access.

The wins are evenly split at one benchmark victory each, but the magnitudes differ. The R7’s Vulkan win (21.4%) is significantly larger than the R5’s OpenCL win (13.7%). This asymmetry suggests that while the R5 M255 is a capable OpenCL performer, the R7 Graphics is exceptional in Vulkan, making it the more specialized part for that API. Meanwhile, the R5 M255’s advantage in OpenCL is more modest, indicating a less dramatic performance gap in that workload.

The Verdict

For users prioritizing modern compute APIs, the AMD Radeon R7 Graphics is the clear pick. Its Vulkan score of 5980 is not only 21.4% ahead of the R5 M255 but also places it in the 29th percentile of all GPUs, which is one percentile higher than the R5’s 28th. The R7’s average benchmark score of 4998 also edges out the R5’s 4788, reinforcing its overall superiority in the tested metrics. This makes the R7 Graphics the better choice for systems running Vulkan-based games or compute tasks, despite being an integrated part with a 25 W TDP.

Conversely, the AMD Radeon R5 M255 is the pick for legacy OpenCL workloads. Its 4650 OpenCL score represents a 13.7% advantage over the R7, and its dedicated 2 GB VRAM with 32.00 GB/s bandwidth provides a more predictable memory performance profile than the R7’s system-shared memory. However, the R5’s overall standing is slightly weaker: its average score of 4788 is lower, and its nearest rivals include the NVIDIA GeForce RTX 3080 12 GB at a -0.1% delta, which is a peculiar but data-backed comparison. The R5 also trails the R7 in percentile ranking, sitting at 28th versus 29th percentile.

The data does not support a universal winner. Instead, the choice hinges on the target API. The R7 Graphics is the better all-around part based on average score and Vulkan performance, while the R5 M255 is the superior OpenCL solution. For a system builder or analyst looking at legacy hardware, the R7 Graphics offers a higher ceiling in modern compute, whereas the R5 M255 provides a more traditional discrete GPU experience with dedicated memory. Neither part is a clear upgrade over the other without specifying the workload.

Head-to-Head Benchmarks

The two Geekbench tests provide the only direct comparison points, and they tell opposing stories. In Geekbench OpenCL, the AMD Radeon R5 M255 wins with a score of 4650 against the R7 Graphics’ 4015. This represents a delta of -13.7% from the R7’s perspective, meaning the R5 is 13.7% faster in this test. The R5’s dedicated memory subsystem—2 GB DDR3 at 32.00 GB/s—likely plays a role here, as OpenCL kernels often benefit from consistent memory bandwidth without system-level contention. The R5 also has higher raw throughput numbers: its pixel rate is 7.520 GPixel/s and texture rate is 22.56 GTexel/s, compared to the R7’s 5.760 GPixel/s and 17.28 GTexel/s. These specifications, combined with a higher FP32 rating of 721.9 GFLOPS versus 553.0 GFLOPS, explain the R5’s OpenCL advantage.

In Geekbench Vulkan, the tables turn dramatically. The AMD Radeon R7 Graphics scores 5980, a 21.4% lead over the R5 M255’s 4925. This is a remarkable reversal, especially considering the R7’s lower clock speeds—though the R7’s clocks are listed as null, meaning they are not specified in the data, while the R5 runs at a base of 925 MHz and boost of 940 MHz. The R7’s Vulkan dominance cannot be explained by raw compute specifications, as it has the same 384 shading units, 24 TMUs, and 8 ROPs as the R5. Instead, the architecture or driver implementation must favor Vulkan’s asynchronous compute and command buffer handling. The R7 also has a higher average benchmark score of 4998 versus 4788, driven entirely by this Vulkan result, which outweighs its OpenCL deficit in the averaging.

The head-to-head data shows a net tie in wins, but the magnitude of the R7’s Vulkan victory is nearly twice the R5’s OpenCL victory. This suggests that for users running both APIs, the R7 Graphics is the more valuable part, as its Vulkan lead is harder to overcome than the R5’s OpenCL edge.

Specification Differences

The two GPUs differ in several key specifications beyond their performance. The process node is the same at 28 nm, but the foundry differs: the R7 Graphics uses GlobalFoundries, while the R5 M255 uses TSMC. The R7’s chip is “Spectre Lite” with a die size of 245 mm² and 2,410 million transistors, whereas the R5’s chip is “Topaz” with a smaller 125 mm² die and 1,550 million transistors. This makes the R7 a larger, more complex chip despite being integrated, while the R5 is a smaller discrete part. Transistor density also differs: the R7 has 9.8M transistors per mm², while the R5 has 12.4M per mm², indicating the R5’s design is denser due to the TSMC process.

Memory configurations are fundamentally different. The R7 Graphics uses system-shared memory with no dedicated VRAM, while the R5 M255 has 2 GB of DDR3 on a 128-bit bus, providing 32.00 GB/s of bandwidth. The R7’s memory clock and bus width are listed as “System Shared,” and its bandwidth is “System Dependent,” meaning performance varies with the host system’s RAM. The R5 also has a defined base clock of 925 MHz and boost clock of 940 MHz, while the R7’s clocks are not specified in the data. The R5’s memory runs at 1000 MHz with 2 Gbps effective speed.

The bus interface also separates them: the R7 is an IGP with no bus interface (listed as “IGP”), while the R5 uses PCIe 3.0 x8. The R7 has a TDP of 25 W, while the R5’s TDP is not listed. Display outputs differ as well: the R7 is “Motherboard Dependent,” while the R5 has no display output information provided. Finally, the R5 lists FP16 performance at 721.9 GFLOPS (1:1), while the R7 has no FP16 data, though both support DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.2.170.

FAQ

Q: Which GPU has a higher average benchmark score?

A: The AMD Radeon R7 Graphics has an average benchmark score of 4998, which is 4.4% higher than the AMD Radeon R5 M255’s 4788.

Q: How much faster is the R5 M255 in OpenCL?

A: The R5 M255 scores 4650 in Geekbench OpenCL, which is 13.7% higher than the R7 Graphics’ 4015.

Q: What explains the R7 Graphics’ Vulkan advantage?

A: The R7 Graphics scores 5980 in Geekbench Vulkan, a 21.4% lead over the R5 M255’s 4925, despite both having 384 shading units, 24 TMUs, and 8 ROPs. The R7’s larger die (245 mm² vs 125 mm²) and different architecture implementation likely contribute.

Q: Do both GPUs support the same APIs?

A: Yes, both support DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.2.170.

Q: How do their memory systems differ?

A: The R7 Graphics uses system-shared memory with bandwidth listed as “System Dependent,” while the R5 M255 has 2 GB of dedicated DDR3 on a 128-bit bus with 32.00 GB/s bandwidth.

Q: Which GPU has a higher percentile ranking?

A: The R7 Graphics ranks in the 29th percentile of all GPUs, while the R5 M255 ranks in the 28th percentile.

Architecture Differences

The architectural split between these two parts is significant. The AMD Radeon R7 Graphics is built on GCN 2.0 architecture, specifically the “Spectre Lite” chip, and is part of the GCN 2.0 IGP generation known as Kaveri. It uses a 28 nm process from GlobalFoundries and contains 2,410 million transistors on a 245 mm² die. The R5 M255, in contrast, uses GCN 3.0 architecture with the “Topaz” chip, belonging to the Gem System (R5 M200) generation. It is fabricated by TSMC on a 28 nm process, with 1,550 million transistors on a smaller 125 mm² die. This makes the R7 a larger, more transistor-heavy design, while the R5 is denser at 12.4M transistors per mm² versus the R7’s 9.8M per mm².

Both GPUs share identical compute unit configurations: 384 shading units, 24 TMUs, and 8 ROPs. However, their clock speeds and memory architectures diverge. The R5 M255 has defined clocks of 925 MHz base and 940 MHz boost, with memory at 1000 MHz (2 Gbps effective), while the R7’s clocks are not specified in the data. The R7 relies entirely on system-shared memory, making its bandwidth dependent on the host system, whereas the R5 has dedicated 2 GB DDR3 with a fixed 32.00 GB/s bandwidth. This gives the R5 a more predictable memory performance profile, while the R7’s performance scales with system RAM.

The R7’s TDP is listed at 25 W, while the R5’s TDP is not provided. The R7 is an IGP with no bus interface, while the R5 uses PCIe 3.0 x8. The R7’s display outputs are motherboard-dependent, whereas the R5 has no display output data. Both are end-of-life products, with the R7 released in February 2014 and the R5 in October 2014. The R7’s predecessor is TeraScale 3 IGP and its successor is GCN 3.0 IGP, while the R5’s predecessor is Solar System and successor is Polaris Mobile. These architectural differences—GCN 2.0 versus GCN 3.0, GlobalFoundries versus TSMC, integrated versus discrete—explain the divergent benchmark results, particularly the R7’s strong Vulkan showing despite its lower raw compute specifications.