AMD Radeon HD 8870M vs AMD Radeon R9 M265X Comparison

The AMD Radeon R9 M265X and AMD Radeon HD 8870M are two closely matched mobile GPUs from different generations, both built on the same Venus chip. The benchmark data shows the R9 M265X holds a narrow but clear edge in raw compute performance, scoring 8851 in Geekbench OpenCL compared to the HD 8870M’s 8462. That 4.6% delta places the R9 M265X slightly ahead, though both cards occupy nearly identical performance percentiles—44th and 43rd percentile respectively—meaning real-world differences will be modest. The R9 M265X is the newer part, released in March 2014, while the HD 8870M arrived a year earlier, but both are end-of-life products today. The verdict hinges on whether that single-digit performance gap matters for your use case, since the underlying architecture, memory configuration, and feature set are virtually identical.

The Verdict

The data points to the AMD Radeon R9 M265X as the default pick for anyone prioritizing raw compute throughput. Its Geekbench OpenCL score of 8851 beats the HD 8870M’s 8462 by 4.6%, and it edges out the NVIDIA GeForce RTX 3050 A Mobile (8746) and GTX 460 v2 (8743) in the nearest rival list. However, the margin is slim—within the same performance class, as both cards sit just one percentile apart (44 vs 43). The HD 8870M is not a slouch; its score of 8462 is virtually tied with the NVIDIA GeForce MX330 (8458) and AMD Radeon 880M (8436), making it a competent option for lighter workloads.

Choose the R9 M265X if you want the faster of the two in compute tasks, especially since it also carries a newer generation label ("Gem System") and a higher memory clock. Choose the HD 8870M if you are constrained by platform compatibility or find it at a significantly better system price—though this database does not track cost, the performance difference is small enough that either will serve similar purposes. For gaming, the 16 ROPs and 40 TMUs on both cards suggest identical rasterization ceilings, so the R9 M265X’s advantage is purely in shader-bound scenarios. In short, the R9 M265X wins on paper, but the HD 8870M remains a viable alternative for those already invested in its ecosystem.

Where Each One Wins

The R9 M265X wins the only head-to-head benchmark recorded, the Geekbench OpenCL test, with a 4.6% higher score (8851 vs 8462). This advantage likely stems from its higher effective memory speed—4 Gbps effective versus the HD 8870M’s 4.5 Gbps effective—though the HD 8870M actually has a higher memory clock in MHz (1125 MHz vs 1000 MHz). Wait, the data shows the R9 M265X has a lower base clock (575 MHz vs 725 MHz) and lower boost clock (625 MHz vs 775 MHz), yet it still scores higher. That is counterintuitive, suggesting the R9 M265X benefits from architectural refinements in the GCN 1.0 implementation or better driver optimization for OpenCL.

The HD 8870M wins on raw clock speed and memory bandwidth. Its base clock of 725 MHz and boost of 775 MHz are substantially higher than the R9 M265X’s 575/625 MHz, and its 72.00 GB/s bandwidth outpaces the R9 M265X’s 64.00 GB/s. This translates to higher pixel rate (12.40 GPixel/s vs 10.00 GPixel/s) and texture rate (31.00 GTexel/s vs 25.00 GTexel/s). For fill-rate-bound workloads—like older games with heavy texture usage or pixel shaders—the HD 8870M should theoretically pull ahead. Yet the benchmark data does not support that, meaning the R9 M265X’s efficiency or driver maturity compensates for its lower clocks.

Architecture Differences

Both GPUs share the same Venus chip and GCN 1.0 architecture, manufactured on TSMC’s 28 nm process with 1,500 million transistors on a 123 mm² die. Transistor density is identical at 12.2M per mm². The shading units (640), TMUs (40), and ROPs (16) are all the same, so the compute core layout is unchanged. The key differences lie in clock speeds and memory configuration.

The R9 M265X runs at a base clock of 575 MHz and boost of 625 MHz, significantly lower than the HD 8870M’s 725/775 MHz. Its memory runs at 1000 MHz with 4 Gbps effective speed, yielding 64.00 GB/s bandwidth over a 128-bit bus. The HD 8870M uses faster memory at 1125 MHz (4.5 Gbps effective), delivering 72.00 GB/s on the same 128-bit bus. Both have 2 GB of GDDR5.

The generations differ: the R9 M265X belongs to the "Gem System" (R9 M200) family, while the HD 8870M is from "Solar System" (HD 8800M). The R9 M265X's predecessor is "Solar System," and its successor is "Polaris Mobile." The HD 8870M's predecessor is "London," and its successor is "Gem System." This lineage suggests the R9 M265X is a refined iteration of the same silicon. Both support DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.170, so API feature parity is complete. The PCIe 3.0 x16 interface is also identical on both.

FAQ

Q: Which GPU has a higher benchmark score?

A: The AMD Radeon R9 M265X scores 8851 in Geekbench OpenCL, while the AMD Radeon HD 8870M scores 8462, giving the R9 M265X a 4.6% advantage.

Q: Are these GPUs based on the same chip?

A: Yes, both use the Venus chip with GCN 1.0 architecture, 1,500 million transistors, and a 123 mm² die size on a 28 nm process.

Q: Which GPU has faster memory?

A: The HD 8870M has faster memory with a 1125 MHz clock (4.5 Gbps effective) and 72.00 GB/s bandwidth, compared to the R9 M265X’s 1000 MHz (4 Gbps effective) and 64.00 GB/s.

Q: Do they support the same APIs?

A: Yes, both support DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.170, with identical PCIe 3.0 x16 interfaces.

Q: Which GPU has higher clock speeds?

A: The HD 8870M runs at 725 MHz base and 775 MHz boost, while the R9 M265X runs at 575 MHz base and 625 MHz boost, making the HD 8870M significantly faster on paper.

Q: How do they compare to rival GPUs?

A: The R9 M265X is 1.2% ahead of the NVIDIA GeForce RTX 3050 A Mobile (8746) and GTX 460 v2 (8743), while the HD 8870M is 0.1% ahead of the NVIDIA GeForce MX330 (8458) and 0.3% ahead of the AMD Radeon 880M (8436).

Head-to-Head Benchmarks

The only recorded head-to-head benchmark is Geekbench OpenCL, and it shows the R9 M265X winning with a score of 8851 against the HD 8870M’s 8462, a delta of 4.6%. This is the decisive metric in this comparison, and it favors the newer card despite its lower clock speeds. The R9 M265X’s 8851 score places it 1.2% above the NVIDIA GeForce RTX 3050 A Mobile (8746) and GTX 460 v2 (8743), and just 0.1% below the AMD Radeon Pro WX 5100 (8863). Meanwhile, the HD 8870M’s 8462 score is nearly identical to the NVIDIA GeForce MX330 (8458, +0.1%) and the AMD Radeon 880M (8436, +0.3%), but 1.1% below the Intel Arc A380 (8558).

The biggest win for the R9 M265X is this 4.6% lead in compute performance, which is notable given the HD 8870M’s higher clocks (775 MHz boost vs 625 MHz) and higher memory bandwidth (72.00 GB/s vs 64.00 GB/s). This suggests the R9 M265X’s architecture achieves better instructions-per-clock or benefits from driver maturity. For the HD 8870M, the theoretical wins are in fill-rate metrics—its 12.40 GPixel/s and 31.00 GTexel/s outperform the R9 M265X’s 10.00 GPixel/s and 25.00 GTexel/s—but these do not translate to a benchmark victory. In practical terms, the R9 M265X is the faster card for compute-heavy tasks like OpenCL workloads, while the HD 8870M’s higher clocks might offer marginal advantages in specific gaming scenarios that are not captured by this single test. Given that both cards share identical core counts (640 shading units, 40 TMUs, 16 ROPs), the R9 M265X’s victory comes down to efficiency rather than raw specs.