AMD Radeon R9 M395X vs NVIDIA GeForce RTX 3080 Mobile Comparison

AMD Radeon R9 M395X and NVIDIA GeForce RTX 3080 Mobile represent two very different eras of mobile graphics, separated by nearly six years of architectural evolution. The data shows a decisive performance gap, with the RTX 3080 Mobile winning the only shared benchmark by a massive margin. This comparison highlights how far mobile GPU technology has advanced, not just in raw speed but in feature set and efficiency.

Head-to-Head Benchmarks

The database contains one directly comparable benchmark between these two GPUs: Geekbench OpenCL. This is a compute-focused test that measures raw throughput, and the results are stark. The NVIDIA GeForce RTX 3080 Mobile scores 104,831 points, while the AMD Radeon R9 M395X manages only 17,829 points. This represents an 83% deficit for the older AMD part, meaning the RTX 3080 Mobile delivers nearly six times the compute performance in this workload. The delta is so large that it reflects not just architectural improvements but a fundamental shift in what a mobile GPU can accomplish.

For context, the R9 M395X sits at the 71st percentile of all GPUs in the database, with an average benchmark score of 25,891. Its nearest rivals include the AMD FirePro W7100 (25,856, just 0.1% behind) and the AMD Radeon RX 6750 XT (26,011, only 0.5% ahead). Interestingly, the R9 M395X also edges out the NVIDIA GeForce RTX 3080 Ti Mobile by 0.6% in average score, though that comparison is based on a different set of benchmarks. The RTX 3080 Mobile, despite winning the OpenCL test decisively, sits at the 69th percentile overall with an average score of 23,628. Its nearest rivals include the NVIDIA GeForce GTX TITAN Z (23,736, 0.5% ahead) and the AMD Radeon RX 9070 (23,877, 1% ahead). This suggests that while the RTX 3080 Mobile excels in compute-heavy OpenCL tasks, its overall benchmark profile is more varied.

The 83% delta in OpenCL is the single most important data point in this comparison. It shows that the RTX 3080 Mobile is not just faster, it is in a completely different performance class. The R9 M395X was competitive in its era, but it cannot keep pace with modern compute workloads.

FAQ

Q: Which GPU has a higher average benchmark score?

A: The AMD Radeon R9 M395X has a higher average benchmark score at 25,891, compared to 23,628 for the NVIDIA GeForce RTX 3080 Mobile. However, this average is calculated from different benchmark suites, so it does not directly reflect head-to-head performance.

Q: What is the performance difference in the shared OpenCL benchmark?

A: The NVIDIA GeForce RTX 3080 Mobile scores 104,831 in Geekbench OpenCL, while the AMD Radeon R9 M395X scores 17,829. The RTX 3080 Mobile wins by 83%, a massive margin that indicates a generational leap in compute capability.

Q: How do these GPUs compare in terms of memory bandwidth?

A: The RTX 3080 Mobile offers 448.0 GB/s of bandwidth with GDDR6 memory, while the R9 M395X offers 160.0 GB/s with GDDR5. Both use a 256-bit memory bus and have 8 GB of memory, but the newer NVIDIA part delivers nearly three times the bandwidth.

Q: Which GPU supports ray tracing and tensor cores?

A: Only the NVIDIA GeForce RTX 3080 Mobile includes dedicated ray tracing cores (48) and tensor cores (192). The AMD Radeon R9 M395X, based on older GCN 3.0 architecture, has neither of these hardware features.

Q: What is the difference in transistor count between the two chips?

A: The NVIDIA GA104 chip in the RTX 3080 Mobile contains 17,400 million transistors, while the AMD Amethyst chip in the R9 M395X contains 5,000 million. This 3.5x difference in transistor count is a major factor in the performance gap.

Q: How do their DirectX support levels differ?

A: The RTX 3080 Mobile supports DirectX 12 Ultimate (12_2), while the R9 M395X supports DirectX 12 (12_0). This means the NVIDIA GPU can utilize more advanced DirectX 12 features, including hardware ray tracing and mesh shaders.

Architecture Differences

The architectural divide between these two GPUs is vast. The AMD Radeon R9 M395X is built on GCN 3.0 architecture, using the Amethyst chip fabricated on a 28 nm process at TSMC. This is an older design that predates many modern graphics features. The chip contains 5,000 million transistors on a 366 mm² die, resulting in a transistor density of 13.7 million per square millimeter. The NVIDIA GeForce RTX 3080 Mobile, in contrast, uses the Ampere architecture with the GA104 chip, fabricated on an 8 nm process at Samsung. This newer process allows for 17,400 million transistors on a 392 mm² die, achieving a density of 44.4 million per square millimeter. The higher density and transistor count enable the Ampere chip to pack far more compute resources into a similar physical footprint.

The compute resources differ dramatically. The R9 M395X has 2,048 shading units, 128 texture mapping units, and 32 raster output units. The RTX 3080 Mobile triples the shading units to 6,144, increases TMUs to 192, and triples ROPs to 96. Additionally, the NVIDIA GPU includes 48 ray tracing cores and 192 tensor cores, hardware that the AMD part lacks entirely. These specialized cores enable features like real-time ray tracing and AI-accelerated workloads, which are simply impossible on the older GCN architecture. The FP32 compute throughput tells the story: the RTX 3080 Mobile delivers 18.98 TFLOPS, while the R9 M395X manages only 2.961 TFLOPS. Both GPUs have a 1:1 FP16 to FP32 ratio, but the NVIDIA part is over six times faster in both.

The memory subsystems also reflect the architectural gap. The R9 M395X uses GDDR5 memory at 5 Gbps effective, offering 160.0 GB/s of bandwidth. The RTX 3080 Mobile uses faster GDDR6 at 14 Gbps effective, delivering 448.0 GB/s. This nearly threefold increase in bandwidth is crucial for modern games and compute workloads that demand rapid data movement. The API support also shows the generational difference: the R9 M395X supports DirectX 12 (12_0) and Vulkan 1.2.170, while the RTX 3080 Mobile supports DirectX 12 Ultimate (12_2) and Vulkan 1.4, enabling more advanced rendering techniques and better driver optimization.

Specification Differences

The recorded specifications reveal a clear generational divide across nearly every measurable category. The process node shrinks from 28 nm on the AMD part to 8 nm on the NVIDIA part, enabling the massive increase in transistor count. The R9 M395X has a memory clock of 1250 MHz (5 Gbps effective), while the RTX 3080 Mobile runs at 1750 MHz (14 Gbps effective), a 40% increase in raw clock speed. The base and boost clocks for the NVIDIA GPU are 1110 MHz and 1545 MHz respectively, while the AMD GPU has no recorded base or boost clock values, only its memory clock.

The pixel rate jumps from 23.14 GPixel/s on the R9 M395X to 148.3 GPixel/s on the RTX 3080 Mobile, and the texture rate jumps from 92.54 GTexel/s to 296.6 GTexel/s. Both GPUs have 8 GB of memory and a 256-bit bus width, but the memory type and bandwidth differ significantly. The TDP also differs: the R9 M395X is rated at 75 W, while the RTX 3080 Mobile draws 115 W. This higher power draw is a trade-off for the substantial performance increase. The bus interface advances from PCIe 3.0 x16 on the AMD part to PCIe 4.0 x16 on the NVIDIA part, offering double the bandwidth for data transfer to the CPU. Both are end-of-life products, but their release dates are separated by nearly six years: May 2015 for the R9 M395X and January 2021 for the RTX 3080 Mobile.

Where Each One Wins

The data records only one head-to-head benchmark, and the NVIDIA GeForce RTX 3080 Mobile wins it decisively. In Geekbench OpenCL, the RTX 3080 Mobile is 83% faster than the R9 M395X. This makes the use case split fairly one-sided. The RTX 3080 Mobile is the clear choice for compute-heavy applications, modern gaming with DirectX 12 Ultimate features, and any workload that can leverage ray tracing or tensor cores. Its 6,144 shading units and 192 tensor cores make it well-suited for AI inference, machine learning tasks, and content creation workloads that use GPU acceleration.

The AMD Radeon R9 M395X, despite its lower performance, does occupy a niche. Its 75 W TDP means it could be found in thinner laptops with less robust cooling solutions. The R9 M395X also has a higher percentile ranking (71st) than the RTX 3080 Mobile (69th), based on average benchmark scores, though this is due to the different benchmark suites used. For users running legacy applications that are optimized for GCN architecture or who need a GPU that draws less power, the R9 M395X could still serve a purpose. However, in the only direct comparison available, the NVIDIA part wins outright, and its architectural advantages suggest it would win in most modern workloads.

The Verdict

The data presents an unambiguous conclusion: the NVIDIA GeForce RTX 3080 Mobile is the superior GPU by a wide margin. In the sole shared benchmark, it outperforms the AMD Radeon R9 M395X by 83%, a gap that reflects not just incremental improvements but a complete architectural overhaul. The RTX 3080 Mobile offers six times the FP32 compute throughput, nearly three times the memory bandwidth, and dedicated hardware for ray tracing and AI workloads. It supports the latest DirectX 12 Ultimate API and uses a modern 8 nm process with over three times the transistor count.

For users seeking maximum performance in modern games, compute tasks, or creative applications, the RTX 3080 Mobile is the clear choice. Its higher 115 W TDP is a reasonable trade-off for the substantial performance gains. The R9 M395X, with its 75 W TDP and GCN 3.0 architecture, is a relic of an older era. It may still handle older games and basic compute tasks, and its 71st percentile ranking shows it was competitive in its time. But the data shows that the RTX 3080 Mobile is not just faster, it is in a different performance class entirely. Anyone choosing between these two GPUs today should select the RTX 3080 Mobile without hesitation, as the benchmark results leave no room for ambiguity.