AMD Radeon R6 M255DX vs AMD Radeon R8 M445DX Comparison

AMD Radeon R6 M255DX and AMD Radeon R8 M445DX are both end-of-life integrated graphics solutions from AMD, but they target different performance tiers within the same hybrid system family. The R8 M445DX holds a clear performance lead in raw compute benchmarks, but the R6 M255DX is not far behind, making the choice between them a matter of specific workload priorities. Benchmark data shows the R8 M445DX scoring 4727 in Geekbench OpenCL, while the R6 M255DX achieves 4867 in Geekbench Vulkan, representing a 2.9% advantage for the older part in its tested API. These are different test suites, so direct comparison requires careful interpretation of what each score represents.

Head-to-Head Benchmarks

The most significant finding is that these two GPUs are separated by a single benchmark result each, and those results come from different testing methodologies. The R6 M255DX posts a Geekbench Vulkan score of 4867, which places it in the 28th percentile of all GPUs. Its nearest rival is the NVIDIA GeForce RTX 5060 Ti 8 GB, which scores 4901, meaning the R6 M255DX trails that modern card by a negligible 0.7%. It also edges out the NVIDIA GeForce GTX 560M (4855) by 0.2% and the NVIDIA GeForce 940MX (4844) by 0.5%. The R6 M255DX is the stronger part in this comparison when looking at its sole benchmark, as it beats three of its four nearest rivals.

The R8 M445DX, meanwhile, achieves a Geekbench OpenCL score of 4727, which slots it into the 27th percentile of all GPUs. Its nearest rival is the AMD Radeon R5 M255, which scores 4788, giving the R8 M445DX a 1.3% deficit against that card. It also trails the AMD Radeon R5 M335 (4752) by 0.5% and the NVIDIA GeForce RTX 3080 12 GB (4791) by 1.3%. The only card it beats among its nearest rivals is the NVIDIA Quadro P400, which scores 4684, giving the R8 M445DX a 0.9% advantage. This pattern shows the R8 M445DX sitting at the bottom of its immediate competitive cluster, whereas the R6 M255DX sits near the top of its own.

Cross-referencing the two results, the R6 M255DX's Vulkan score of 4867 is 140 points higher than the R8 M445DX's OpenCL score of 4727. That is a 2.9% gap in favor of the R6 M255DX, but it is crucial to note that Vulkan and OpenCL are not directly comparable workloads. The R6 M255DX also has a higher average benchmark score of 4867 versus 4727 for the R8 M445DX, reinforcing that the older part performs better in its tested scenario. However, the R8 M445DX compensates with a significantly higher boost clock of 1021 MHz versus 855 MHz for the R6 M255DX, which explains its superior pixel and texture throughput rates.

In terms of raw throughput, the R8 M445DX is decisively ahead. It produces 8.168 GPixel/s of pixel rate and 20.42 GTexel/s of texture rate, compared to 6.840 GPixel/s and 17.10 GTexel/s for the R6 M255DX. That represents a 19.4% advantage in pixel fill and a 19.4% advantage in texture fill for the R8 M445DX. The FP32 compute figures tell a similar story: the R8 M445DX delivers 653.4 GFLOPS, which is 19.4% higher than the R6 M255DX's 547.2 GFLOPS. These numbers indicate that the R8 M445DX is substantially faster at raw graphics operations, even though its measured benchmark score is lower.

The Verdict

The data points to the R8 M445DX as the more capable graphics processor for most tasks, despite its lower benchmark score. Its 19.4% advantage in pixel rate, texture rate, and FP32 compute over the R6 M255DX is a consistent pattern across three separate metrics, making it the stronger choice for any workload that stresses fill rates or shader compute. The higher boost clock of 1021 MHz, up from 855 MHz, directly drives these gains. If the goal is gaming or GPU-accelerated compute, the R8 M445DX is the better pick.

The R6 M255DX, however, is not without merit. Its Vulkan benchmark score of 4867 is higher than the R8 M445DX's OpenCL score of 4727, and it sits in a higher percentile (28th versus 27th). This suggests that in Vulkan-based applications, the R6 M255DX may perform competitively or even better than the R8 M445DX, which was only tested in OpenCL. Users who prioritize Vulkan compatibility or run applications that leverage that API might find the R6 M255DX to be the better option. Its nearest rival comparison also shows it beating three of four competitors, whereas the R8 M445DX only beats one of four.

For general-purpose use, the R8 M445DX is the recommended choice due to its superior raw throughput metrics. The R6 M255DX is the choice for users specifically targeting Vulkan workloads or who value a slightly higher benchmark percentile. Neither GPU is a standout performer, as both sit in the bottom third of all GPUs, but the R8 M445DX's hardware specifications give it a clear edge in most scenarios.

FAQ

Q: Which GPU has a higher Geekbench Vulkan score?

A: The AMD Radeon R6 M255DX scores 4867 in Geekbench Vulkan, while the AMD Radeon R8 M445DX has no Vulkan benchmark result in the data.

Q: What is the Geekbench OpenCL score for the R8 M445DX, and how does it compare to its nearest rival?

A: The R8 M445DX scores 4727 in Geekbench OpenCL, which is 0.5% lower than the AMD Radeon R5 M335's score of 4752 and 0.9% higher than the NVIDIA Quadro P400's score of 4684.

Q: How do the pixel rates of the two GPUs compare?

A: The R8 M445DX has a pixel rate of 8.168 GPixel/s, which is 19.4% higher than the R6 M255DX's pixel rate of 6.840 GPixel/s.

Q: What are the boost clock speeds for each GPU?

A: The R6 M255DX has a boost clock of 855 MHz, while the R8 M445DX has a boost clock of 1021 MHz.

Q: Which GPU has a higher FP32 compute performance?

A: The R8 M445DX delivers 653.4 GFLOPS, which is 19.4% higher than the R6 M255DX's 547.2 GFLOPS.

Q: What is the percentile ranking for each GPU?

A: The R6 M255DX is in the 28th percentile of all GPUs, while the R8 M445DX is in the 27th percentile.

Specification Differences

The two GPUs share several core specifications but diverge on key performance parameters. Both have 320 shading units, 20 texture mapping units, and 8 raster operation units. They also share the same base clock of 780 MHz and both use system-shared memory with a system-dependent bandwidth. The critical differences are in boost clock, throughput rates, and compute capabilities. The R8 M445DX has a boost clock of 1021 MHz, which is 166 MHz higher than the R6 M255DX's 855 MHz. This translates to a pixel rate of 8.168 GPixel/s versus 6.840 GPixel/s, and a texture rate of 20.42 GTexel/s versus 17.10 GTexel/s. The FP32 compute is 653.4 GFLOPS for the R8 M445DX and 547.2 GFLOPS for the R6 M255DX.

The R8 M445DX also supports FP16 compute at 653.4 GFLOPS with a 1:1 ratio, while the R6 M255DX has no FP16 capability listed. Both GPUs are integrated graphics with an IGP slot width and portable-device-dependent display outputs. The R6 M255DX was released on January 6, 2014, while the R8 M445DX came later on May 14, 2016. Both are marked as end-of-life products, and neither has a launch MSRP listed.

Architecture Differences

The architectural split is clear: the R6 M255DX uses GCN 1.0 architecture on the Jet chip, while the R8 M445DX uses GCN 3.0 architecture on the Meso chip. Both are built on a 28 nm process at TSMC, but the transistor count differs substantially. The R6 M255DX has 690 million transistors on a 56 mm² die, resulting in a transistor density of 12.3M per mm². The R8 M445DX has 1,550 million transistors on a 125 mm² die, giving it a density of 12.4M per mm². This means the R8 M445DX has more than double the transistor count and a larger die, despite the similar density.

The R6 M255DX belongs to the "Gem System Hybrid (Rx M200)" generation, while the R8 M445DX belongs to the "Gem System Hybrid (Rx M400)" generation. In terms of API support, the R6 M255DX supports DirectX 12 (11_1), while the R8 M445DX supports DirectX 12 (12_0). Both support OpenGL 4.6 and Vulkan 1.2.170. The R8 M445DX's newer GCN 3.0 architecture and superior DirectX 12 feature level represent a generational step forward, even though both remain integrated graphics solutions.

Where Each One Wins

The R8 M445DX wins on raw performance metrics across the board. Its 19.4% higher pixel rate and texture rate make it the better choice for resolution-heavy rendering and texture-intensive workloads. The 19.4% higher FP32 compute means it handles shader math and general compute tasks faster. The additional FP16 support at 653.4 GFLOPS opens up workloads that the R6 M255DX cannot handle at all. For gaming at playable settings, video encoding, or any GPU-accelerated compute, the R8 M445DX is the superior option.

The R6 M255DX wins on benchmark score and percentile placement. Its Geekbench Vulkan score of 4867 is higher than the R8 M445DX's OpenCL score of 4727, and it ranks in the 28th percentile versus the 27th. The R6 M255DX also compares more favorably to its nearest rivals, beating three of four competitors, while the R8 M445DX only beats one of four. This suggests that in Vulkan-specific applications, the R6 M255DX might offer better real-world performance than its older architecture would suggest. Users who run Vulkan-based games or applications should consider the R6 M255DX, while those who need maximum raw throughput should choose the R8 M445DX.