AMD Radeon Pro 450 vs AMD Radeon R9 M275X Comparison

AMD Radeon Pro 450 and AMD Radeon R9 M275X are two end-of-life mobile graphics solutions that, despite their similar average benchmark scores, target very different computing eras. The Pro 450 is a 14nm GCN 4.0 part designed for modern professional Mac workflows, while the R9 M275X is a 28nm GCN 1.0 chip from the earlier R9 M200 generation. Their head-to-head data reveals a split decision: the older R9 M275X dominates in OpenCL compute, while the newer Pro 450 takes the lead in Vulkan graphics. This creates an interesting case study in how architectural evolution affects real-world performance across different API workloads.

Where Each One Wins

The benchmark results split cleanly along API lines. The AMD Radeon R9 M275X is the clear winner for OpenCL compute workloads, posting a score of 11,200 compared to the Pro 450’s 9,002. That is a substantial 19.6% lead for the older card, suggesting that its raw FP32 throughput and memory subsystem configuration are better suited for general-purpose GPU computing tasks that leverage OpenCL. The R9 M275X also has a higher theoretical peak in several key metrics, including FP32 (1,184.0 GFLOPS vs 1,024.0 GFLOPS), pixel rate (14.80 GPixel/s vs 12.80 GPixel/s), and texture rate (37.00 GTexel/s vs 32.00 GTexel/s).

Conversely, the AMD Radeon Pro 450 wins the Vulkan graphics battle. In the geekbench_vulkan test, the Pro 450 scores 10,518 against the R9 M275X’s 9,964, a 5.6% advantage. This win is notable because the Pro 450 has lower theoretical compute and fillrate numbers, yet it still manages to outperform in a modern graphics API. This suggests that architectural improvements in GCN 4.0, such as better driver optimization or more efficient instruction scheduling, provide a tangible benefit in Vulkan that raw clock speeds cannot overcome. For users running Vulkan-based games or applications, the Pro 450 is the better choice despite its lower peak specifications.

Architecture Differences

The two GPUs represent two distinct generations of AMD’s Graphics Core Next (GCN) architecture. The Radeon Pro 450 is built on GCN 4.0 using a 14 nm process at GlobalFoundries, while the Radeon R9 M275X uses the older GCN 1.0 architecture on a 28 nm process at TSMC. This process shrink allows the Pro 450 to pack 3,000 million transistors into the same 123 mm² die size as the R9 M275X, which only contains 1,500 million transistors. The transistor density tells the story clearly: the Pro 450 achieves 24.4M / mm² compared to the R9 M275X’s 12.2M / mm², a doubling of density that reflects the newer fabrication technology.

Both cards feature identical core configurations: 640 shading units, 40 texture mapping units, and 16 raster output units. They also share the same 2 GB GDDR5 memory on a 128-bit bus. However, the memory clocks differ, with the Pro 450 running at 1270 MHz (5.1 Gbps effective) versus the R9 M275X’s 1125 MHz (4.5 Gbps effective). This gives the Pro 450 a memory bandwidth of 81.28 GB/s compared to 72.00 GB/s for the R9 M275X. The R9 M275X compensates with higher base and boost clocks (900 MHz base, 925 MHz boost) while the Pro 450’s clock speeds are not specified in the data.

API support is another key differentiator. The Pro 450 supports DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.3, while the R9 M275X is limited to DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.170. The newer Vulkan version on the Pro 450 aligns with its better Vulkan benchmark performance. Additionally, the Pro 450 is a 35 W MXM Module with a PCIe 3.0 x8 interface, whereas the R9 M275X uses PCIe 3.0 x16 and has no TDP or slot width specified.

Head-to-Head Benchmarks

The head-to-head comparison offers only two data points, but they are revealing. In geekbench_opencl, the R9 M275X wins decisively with a score of 11,200 against the Pro 450’s 9,002, yielding a delta of -19.6% from the Pro 450’s perspective. This is a significant margin that cannot be explained by clock speeds alone. The R9 M275X’s boost clock of 925 MHz and higher FP32 rate (1,184.0 GFLOPS) likely contribute, but the magnitude of the win suggests that the older GCN 1.0 architecture may have more efficient OpenCL execution paths or that the Pro 450’s drivers are less optimized for this legacy API.

In geekbench_vulkan, the tables turn. The Pro 450 scores 10,518 versus the R9 M275X’s 9,964, a 5.6% advantage. This is a smaller margin than the OpenCL gap, but it is still meaningful. The Pro 450’s support for Vulkan 1.3 (versus 1.2.170 on the R9 M275X) likely plays a role, as newer API versions often include performance improvements and better resource management. The Pro 450 also has higher memory bandwidth (81.28 GB/s vs 72.00 GB/s), which may help in Vulkan workloads that are more memory-intensive than compute-heavy OpenCL tasks.

It is worth remembering the average benchmark scores for both cards are remarkably close: 10,804 for the Pro 450 and 10,582 for the R9 M275X, a difference of just over 2%. Both sit at the 49th percentile of all GPUs, placing them in the mid-range of the performance spectrum. The nearest rivals for the Pro 450 include the NVIDIA Quadro K2200 (avg score 10,761, delta 0.4%) and the NVIDIA GeForce MX350 (avg score 10,883, delta -0.7%), while the R9 M275X’s rivals include the AMD Radeon RX 6600S (avg score 10,629, delta -0.4%) and the AMD Radeon RX 550X (avg score 10,481, delta 1%). These rival comparisons show both cards are competitive with each other and with similarly positioned GPUs.

FAQ

Q: Which GPU has better raw compute performance?

A: The Radeon R9 M275X wins in OpenCL with a score of 11,200 versus 9,002 for the Pro 450, a 19.6% advantage. It also has higher FP32 throughput at 1,184.0 GFLOPS compared to 1,024.0 GFLOPS.

Q: Does the Pro 450 have any advantage in modern graphics APIs?

A: Yes, the Pro 450 wins the Vulkan benchmark (10,518 vs 9,964) and supports Vulkan 1.3, while the R9 M275X is limited to Vulkan 1.2.170. This suggests better performance in Vulkan-based applications.

Q: Are these two GPUs similar in overall performance?

A: Yes, their average benchmark scores are very close: 10,804 for the Pro 450 and 10,582 for the R9 M275X. Both are at the 49th percentile of all GPUs.

Q: What are the key architectural differences?

A: The Pro 450 uses GCN 4.0 on a 14 nm process with 3,000 million transistors, while the R9 M275X uses GCN 1.0 on 28 nm with 1,500 million transistors. Both have 640 shading units, 40 TMUs, and 16 ROPs.

Q: Which GPU has better memory bandwidth?

A: The Pro 450 has higher memory bandwidth at 81.28 GB/s compared to 72.00 GB/s for the R9 M275X, due to its faster memory clock (1270 MHz vs 1125 MHz).

Q: Do they support the same DirectX version?

A: No, the Pro 450 supports DirectX 12 (12_0) while the R9 M275X is limited to DirectX 12 (11_1). Both support OpenGL 4.6.

Specification Differences

The two cards differ in several key specification fields. The process node is a major divergence: the Pro 450 uses 14 nm at GlobalFoundries, while the R9 M275X uses 28 nm at TSMC. This leads to a transistor count difference of 3,000 million versus 1,500 million, despite both having a die size of 123 mm². The transistor density is 24.4M / mm² for the Pro 450 and 12.2M / mm² for the R9 M275X.

Clock speeds also differ, with the R9 M275X having explicit base (900 MHz) and boost (925 MHz) clocks, while the Pro 450’s clocks are not specified. Memory clocks are different as well: 1270 MHz (5.1 Gbps effective) for the Pro 450 versus 1125 MHz (4.5 Gbps effective) for the R9 M275X. This results in bandwidths of 81.28 GB/s and 72.00 GB/s, respectively.

Compute rates favor the R9 M275X in most categories: pixel rate (14.80 GPixel/s vs 12.80 GPixel/s), texture rate (37.00 GTexel/s vs 32.00 GTexel/s), and FP32 (1,184.0 GFLOPS vs 1,024.0 GFLOPS). The Pro 450 supports FP16 at 1,024.0 GFLOPS (1:1), while the R9 M275X has no FP16 data. The Pro 450 has a TDP of 35 W and is an MXM Module, while the R9 M275X has no TDP or slot width specified. The bus interface differs: PCIe 3.0 x8 for the Pro 450 and PCIe 3.0 x16 for the R9 M275X. API support varies, with the Pro 450 offering DirectX 12 (12_0) and Vulkan 1.3, versus DirectX 12 (11_1) and Vulkan 1.2.170 for the R9 M275X. The Pro 450’s display outputs are listed as "Portable Device Dependent" while the R9 M275X has no display output data. Their generations differ: "Radeon Pro Mac (400 Series)" for the Pro 450 and "Gem System (R9 M200)" for the R9 M275X.

The Verdict

Based strictly on the data, the choice between these two GPUs depends entirely on the target workload. For OpenCL compute tasks, the AMD Radeon R9 M275X is the superior option, offering a 19.6% higher score and greater theoretical FP32 throughput. This makes it the pick for users running compute-heavy applications that rely on OpenCL, despite its older architecture and lower memory bandwidth.

For Vulkan graphics workloads, the AMD Radeon Pro 450 is the better choice. Its 5.6% higher Vulkan score, combined with Vulkan 1.3 support and higher memory bandwidth, gives it a clear edge in modern graphics APIs. The Pro 450 also benefits from a much newer process node (14 nm vs 28 nm), which likely translates to better power efficiency—a factor supported by its 35 W TDP, though the R9 M275X’s TDP is not disclosed.

Given that the average benchmark scores are nearly identical (10,804 vs 10,582) and both sit at the 49th percentile, the decision comes down to API preference. The Pro 450 is the more forward-looking option, with better Vulkan performance and newer DirectX support, making it suitable for users who prioritize modern graphics APIs. The R9 M275X, while older, remains a strong choice for OpenCL-centric compute workloads where its higher FP32 rate and fillrates provide a tangible advantage. In summary, the Pro 450 wins for Vulkan and modern graphics; the R9 M275X wins for OpenCL compute.