AMD Radeon R9 M395X vs NVIDIA RTX A4000 Comparison

The NVIDIA RTX A4000 and AMD Radeon R9 M395X are separated by nearly six years of GPU architecture, and the benchmark data reflects that gap as a chasm. The only directly comparable compute metric—Geekbench OpenCL—shows the A4000 delivering a score of 105,739 against the M395X’s 17,829. That is a 493.1% delta in favor of the NVIDIA card. In practical terms, the A4000 does in a single pass what the R9 M395X would need roughly six passes to complete. The A4000’s average benchmark score of 26,683 places it in the 72nd percentile of all GPUs, while the M395X’s 25,891 average lands in the 71st percentile—a narrow overall gap that masks the massive per-test discrepancy.

The head-to-head table lists only one shared benchmark, so the overall win tally is 1-0 for the A4000. But that single result is decisive. The 493.1% lead in OpenCL means the A4000 is not merely faster; it is in a different performance class. Looking at the nearest rivals for context, the A4000’s 26,683 average is nearly identical to the AMD Radeon RX 5700 XT 50th Anniversary (26,553, a 0.5% delta) and the NVIDIA GeForce MX550 (26,421, a 1% delta). The M395X’s 25,891 average sits just above the AMD FirePro W7100 (25,856, 0.1% delta) and slightly below the AMD Radeon RX 6750 XT (26,011, a -0.5% delta). In other words, the M395X is competitive with mid-range GPUs from its era, but the A4000 is competing with far more modern silicon.

Where Each One Wins

The A4000 wins the only shared benchmark outright, so its victory is absolute in that comparison. The Geekbench OpenCL result is a compute-heavy workload, and the A4000’s 105,739 score reflects its workstation orientation. The M395X’s 17,829 in the same test shows it is not designed for that kind of parallel processing load. If you look at the A4000’s broader benchmark suite, it also posts strong numbers in Passmark G3D (19,459) and Passmark GPU Compute (9,760), plus Geekbench Vulkan (127,645). Those results are not directly comparable to the M395X because the AMD card lacks Vulkan and Passmark entries, but they indicate where the A4000 excels: 3D rendering, compute, and modern API workloads.

The M395X’s only benchmark entry beyond OpenCL is Geekbench Metal, where it scores 33,953. That is the one area where the AMD card has a data point the A4000 cannot match, because the A4000 has no Metal benchmark listed. The M395X’s 75 W TDP and MXM module form factor also suggest it was built for portable or all-in-one systems, not for workstation towers. Its 8 GB of GDDR5 memory and 160.0 GB/s bandwidth are adequate for its era, but the A4000’s 16 GB GDDR6 at 448.0 GB/s is in a different tier. If you need OpenCL compute, the A4000 is the only choice. If you need Metal support on a legacy AMD platform, the M395X has that specific capability.

Architecture Differences

The architectural gap between these two GPUs is the root cause of their performance disparity. The A4000 uses the GA104 chip on a Samsung 8 nm process, packing 17,400 million transistors into a 392 mm² die. The M395X uses the Amethyst chip on a TSMC 28 nm process, with 5,000 million transistors on a 366 mm² die. That means the A4000 has a transistor density of 44.4M per mm² versus the M395X’s 13.7M per mm²—more than three times the density. The A4000’s Ampere architecture is built for modern workflows, while the M395X’s GCN 3.0 architecture dates back to 2015.

The compute resources tell the same story. The A4000 has 6,144 shading units, 192 TMUs, and 96 ROPs, plus 48 ray tracing cores and 192 tensor cores. The M395X has 2,048 shading units, 128 TMUs, and 32 ROPs, with no ray tracing or tensor cores at all. That is a 3x advantage in shading units, a 1.5x advantage in TMUs, and a 3x advantage in ROPs. The A4000’s FP32 throughput is 19.17 TFLOPS, while the M395X manages 2.961 TFLOPS—a 6.5x difference. The A4000 also supports DirectX 12 Ultimate (12_2) and Vulkan 1.4, whereas the M395X tops out at DirectX 12 (12_0) and Vulkan 1.2.170. The A4000’s pixel rate of 149.8 GPixel/s and texture rate of 299.5 GTexel/s dwarf the M395X’s 23.14 GPixel/s and 92.54 GTexel/s.

FAQ

Q: Which GPU has more memory bandwidth?

A: The NVIDIA RTX A4000 has 448.0 GB/s of bandwidth from 16 GB of GDDR6 on a 256-bit bus. The AMD Radeon R9 M395X has 160.0 GB/s from 8 GB of GDDR5 on the same 256-bit bus. That is a 2.8x advantage for the A4000.

Q: Does the R9 M395X support ray tracing?

A: No. The R9 M395X has no ray tracing cores listed. The RTX A4000 has 48 dedicated ray tracing cores and 192 tensor cores, which are absent from the AMD card.

Q: What is the power draw difference?

A: The RTX A4000 has a 140 W TDP and requires a single 6-pin power connector, with a suggested 300 W PSU. The R9 M395X has a 75 W TDP and uses no power connectors, drawing power entirely from the MXM slot.

Q: Which GPU is better for OpenCL compute?

A: The RTX A4000 scores 105,739 in Geekbench OpenCL versus the R9 M395X’s 17,829. That is a 493.1% lead for the A4000, making it the clear choice for any OpenCL workload.

Q: How do these GPUs compare in overall benchmark percentile?

A: The RTX A4000 sits in the 72nd percentile of all GPUs with an average score of 26,683. The R9 M395X sits in the 71st percentile with an average score of 25,891. Despite the small overall gap, the A4000’s nearest rivals include the RTX 5060 and RX 5700 XT 50th Anniversary, while the M395X is closer to the FirePro W7100.

Q: What are the API differences?

A: The RTX A4000 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The R9 M395X supports DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.2.170. The A4000 also has a Geekbench Vulkan score of 127,645; the M395X has no Vulkan benchmark listed.

Specification Differences

| Field | NVIDIA RTX A4000 | AMD Radeon R9 M395X |

|---|---|---|

| Chip | GA104 | Amethyst |

| Architecture | Ampere | GCN 3.0 |

| Process Node | 8 nm (Samsung) | 28 nm (TSMC) |

| Transistors | 17,400 million | 5,000 million |

| Die Size | 392 mm² | 366 mm² |

| Transistor Density | 44.4M / mm² | 13.7M / mm² |

| Base Clock | 735 MHz | Not listed |

| Boost Clock | 1560 MHz | Not listed |

| Memory Clock | 1750 MHz (14 Gbps effective) | 1250 MHz (5 Gbps effective) |

| Memory Size | 16 GB GDDR6 | 8 GB GDDR5 |

| Memory Bus | 256 bit | 256 bit |

| Memory Bandwidth | 448.0 GB/s | 160.0 GB/s |

| Shading Units | 6,144 | 2,048 |

| TMUs | 192 | 128 |

| ROPs | 96 | 32 |

| RT Cores | 48 | None |

| Tensor Cores | 192 | None |

| Pixel Rate | 149.8 GPixel/s | 23.14 GPixel/s |

| Texture Rate | 299.5 GTexel/s | 92.54 GTexel/s |

| FP32 | 19.17 TFLOPS | 2.961 TFLOPS |

| FP16 | 19.17 TFLOPS (1:1) | 2.961 TFLOPS (1:1) |

| TDP | 140 W | 75 W |

| Slot Width | Single-slot | MXM Module |

| Power Connectors | 1x 6-pin | None |

| Bus Interface | PCIe 4.0 x16 | PCIe 3.0 x16 |

| Display Outputs | 4x DisplayPort 1.4a | Portable Device Dependent |

| DirectX | 12 Ultimate (12_2) | 12 (12_0) |

| Vulkan | 1.4 | 1.2.170 |

| Release Date | 2021-04-11 | 2015-05-04 |

| Predecessor | Quadro Turing | Solar System |

| Successor | Workstation Ada | Polaris Mobile |

The Verdict

The data is unambiguous: the NVIDIA RTX A4000 is the superior GPU for any compute or modern graphics workload. The 493.1% lead in Geekbench OpenCL is not a marginal win; it is a generational leap. The A4000’s 19.17 TFLOPS FP32 versus the M395X’s 2.961 TFLOPS means the NVIDIA card processes over six times the floating-point operations per second. The A4000 also brings 16 GB of GDDR6 memory, 48 ray tracing cores, and 192 tensor cores—features the M395X simply does not have. If you are choosing between these two for a workstation or a modern application, the A4000 is the only rational pick.

The R9 M395X’s case rests entirely on its 75 W TDP and MXM module form factor, which make it suitable for legacy portable systems that cannot accommodate a full-size card. Its Geekbench Metal score of 33,953 gives it a niche capability on Apple platforms that the A4000 does not list. But for everything else—OpenCL, Vulkan, DirectX 12 Ultimate, or raw compute density—the A4000 wins outright. The M395X’s 71st percentile ranking is respectable for a 2015 part, but the A4000’s 72nd percentile comes with far more headroom in modern workloads. Pick the A4000 for performance; pick the M395X only if you are constrained to an old MXM slot and need Metal support.