AMD Radeon Instinct MI25 vs NVIDIA RTX A4500 Comparison

FAQ

Q: How does the NVIDIA RTX A4500 compare to the AMD Radeon Instinct MI25 in overall benchmark performance?

A: The database shows the NVIDIA RTX A4500 has an average benchmark score of 91,671, while the AMD Radeon Instinct MI25 scores 68,562. This places the RTX A4500 in the 93rd percentile of all GPUs, compared to the 90th percentile for the MI25.

Q: What is the most significant benchmark difference between these two cards?

A: In the Geekbench OpenCL test, the RTX A4500 scores 141,837 versus 68,562 for the MI25, a 106.9% advantage. This is the only head-to-head benchmark recorded in the database.

Q: Which card has more memory, and what type of memory does each use?

A: The NVIDIA RTX A4500 has 20 GB of GDDR6 memory on a 320-bit bus, while the AMD Radeon Instinct MI25 has 16 GB of HBM2 memory on a 2048-bit bus. The RTX A4500 achieves 640.0 GB/s bandwidth versus 436.2 GB/s for the MI25.

Q: Do these cards support real-time ray tracing and tensor operations?

A: The NVIDIA RTX A4500 includes 56 ray tracing cores and 224 tensor cores, reflecting its Ampere architecture. The AMD Radeon Instinct MI25 has none, as its GCN 5.0 architecture predates those dedicated hardware blocks.

Q: What are the power requirements for each card?

A: The RTX A4500 has a 200 W TDP with a single 8-pin power connector and a suggested 550 W PSU. The MI25 has a 300 W TDP, requires two 8-pin connectors, and a suggested 700 W PSU.

Q: Which card is newer, and what is the production status of each?

A: The RTX A4500 was released on 2021-11-22, while the MI25 was released on 2017-06-26. Both are listed as end-of-life products in the database.

Architecture Differences

The NVIDIA RTX A4500 is built on the GA102 chip using the Ampere architecture, manufactured on Samsung's 8 nm process. The AMD Radeon Instinct MI25 uses the Vega 10 chip with GCN 5.0 architecture, produced by GlobalFoundries on a 14 nm node. This process gap is substantial: the RTX A4500 packs 28,300 million transistors into a 628 mm² die, yielding a transistor density of 45.1M per mm². The MI25 contains only 12,500 million transistors on a 495 mm² die, for a density of 25.3M per mm². The newer process allows the A4500 to nearly double the transistor count while maintaining a lower 200 W TDP compared to the MI25's 300 W.

The compute pipelines differ fundamentally. The RTX A4500 has 7,168 shading units, 224 texture mapping units, and 96 ROPs. It also carries 56 dedicated ray tracing cores and 224 tensor cores, features entirely absent from the MI25, which has 4,096 shading units, 256 TMUs, and 64 ROPs. The A4500's FP32 throughput is 23.65 TFLOPS, and its FP16 throughput is the same at 23.65 TFLOPS with a 1:1 ratio. The MI25 delivers 12.29 TFLOPS FP32 but reaches 24.58 TFLOPS FP16 using a 2:1 ratio. This means the MI25 actually exceeds the A4500 in raw FP16 compute, though the A4500's tensor cores provide a different path for AI workloads.

Memory architecture also diverges sharply. The A4500 uses 20 GB of GDDR6 across a 320-bit interface at 2000 MHz (16 Gbps effective), producing 640.0 GB/s of bandwidth. The MI25 uses 16 GB of HBM2 on a much wider 2048-bit bus at 852 MHz (1704 Mbps effective), yielding 436.2 GB/s. The A4500's higher effective memory speed compensates for its narrower bus, resulting in greater bandwidth overall.

API support shows generational differences. The RTX A4500 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The MI25 supports DirectX 12 (12_1, not Ultimate), OpenGL 4.6, and Vulkan 1.3. The MI25 has no display outputs at all, making it a compute-only accelerator, while the A4500 provides four DisplayPort 1.4a outputs. The A4500 uses PCIe 4.0 x16, whereas the MI25 uses PCIe 3.0 x16.

Head-to-Head Benchmarks

The database records a single head-to-head comparison: Geekbench OpenCL. The NVIDIA RTX A4500 scores 141,837 against the AMD Radeon Instinct MI25's 68,562. The delta is 106.9%, meaning the A4500 more than doubles the MI25's score in this workload. This is a decisive margin that reflects the architectural and generational advantages of the A4500. The A4500's 23.65 TFLOPS FP32 throughput versus 12.29 TFLOPS for the MI25 aligns with this result, as does the 640.0 GB/s versus 436.2 GB/s memory bandwidth gap.

The A4500 also holds a significant advantage in the percentile rankings, sitting at 93rd versus 90th for the MI25. The average benchmark score of the A4500, 91,671, is 33.7% higher than the MI25's 68,562. While the MI25's FP16 throughput of 24.58 TFLOPS exceeds the A4500's 23.65 TFLOPS, OpenCL workloads in this database appear to favor the A4500's overall balance of compute, memory bandwidth, and driver optimization.

For context, the A4500's nearest rivals include the NVIDIA RTX A4500 Mobile (0.6% ahead), the AMD Radeon Instinct MI60 (0.9% behind), the NVIDIA Quadro GP100 (4.8% ahead), and the AMD Radeon PRO W7600 (5.2% ahead). The MI25's nearest rivals include the Intel Arc A770 (0.4% behind), the NVIDIA CMP 90HX (0.6% behind), the AMD Radeon Pro WX 8200 (1.9% behind), and the NVIDIA Quadro P6000 (2.0% behind). These clusters suggest the MI25 is competitive with mid-range cards of its era, while the A4500 sits in a higher performance tier.

Specification Differences

| Specification | NVIDIA RTX A4500 | AMD Radeon Instinct MI25 |

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

| Architecture | Ampere | GCN 5.0 |

| Process node | 8 nm | 14 nm |

| Foundry | Samsung | GlobalFoundries |

| Transistors | 28,300 million | 12,500 million |

| Die size | 628 mm² | 495 mm² |

| Transistor density | 45.1M / mm² | 25.3M / mm² |

| Base clock | 1050 MHz | 1400 MHz |

| Boost clock | 1650 MHz | 1500 MHz |

| Memory clock | 2000 MHz (16 Gbps effective) | 852 MHz (1704 Mbps effective) |

| Memory size | 20 GB | 16 GB |

| Memory type | GDDR6 | HBM2 |

| Memory bus width | 320 bit | 2048 bit |

| Memory bandwidth | 640.0 GB/s | 436.2 GB/s |

| Shading units | 7168 | 4096 |

| TMUs | 224 | 256 |

| ROPs | 96 | 64 |

| RT cores | 56 | None |

| Tensor cores | 224 | None |

| Pixel rate | 158.4 GPixel/s | 96.00 GPixel/s |

| Texture rate | 369.6 GTexel/s | 384.0 GTexel/s |

| FP32 | 23.65 TFLOPS | 12.29 TFLOPS |

| FP16 | 23.65 TFLOPS (1:1) | 24.58 TFLOPS (2:1) |

| TDP | 200 W | 300 W |

| Power connectors | 1x 8-pin | 2x 8-pin |

| Suggested PSU | 550 W | 700 W |

| Bus interface | PCIe 4.0 x16 | PCIe 3.0 x16 |

| Display outputs | 4x DisplayPort 1.4a | No outputs |

| DirectX | 12 Ultimate (12_2) | 12 (12_1) |

| Vulkan | 1.4 | 1.3 |

| Release date | 2021-11-22 | 2017-06-26 |

The MI25 has a higher base clock (1400 MHz versus 1050 MHz) and slightly higher texture rate (384.0 GTexel/s versus 369.6 GTexel/s), but the A4500 dominates in shading units, ROPs, pixel rate, and FP32 compute. Both cards are dual-slot, similar in physical dimensions (267 mm length, 111-112 mm height), and both are end-of-life. The A4500's predecessor is Quadro Turing and its successor is Workstation Ada; the MI25's predecessor is FirePro Data Center with no successor listed.

Where Each One Wins

The NVIDIA RTX A4500 wins in raw FP32 compute, delivering 23.65 TFLOPS versus 12.29 TFLOPS for the MI25. It also wins decisively in memory bandwidth (640.0 GB/s versus 436.2 GB/s) and pixel throughput (158.4 GPixel/s versus 96.00 GPixel/s). The A4500 is the clear choice for workloads that depend on modern graphics features: its 56 RT cores enable hardware-accelerated ray tracing, and its 224 tensor cores accelerate AI inference and training tasks that the MI25 cannot handle with dedicated hardware. The A4500 also supports DirectX 12 Ultimate and Vulkan 1.4, making it more suitable for current-generation graphics applications. Its display outputs allow it to function as a workstation GPU, while the MI25 has none.

The AMD Radeon Instinct MI25 retains advantages in a few specific areas. Its FP16 throughput of 24.58 TFLOPS exceeds the A4500's 23.65 TFLOPS, and its 2:1 FP16 ratio suggests it was optimized for early deep learning workloads that relied on half-precision compute. The MI25's texture rate of 384.0 GTexel/s is slightly higher than the A4500's 369.6 GTexel/s, and its HBM2 memory, while lower in bandwidth, offers a different latency profile. The MI25 also has a higher base clock at 1400 MHz versus 1050 MHz, though its boost clock of 1500 MHz is lower than the A4500's 1650 MHz.

In practical terms, the A4500 is the stronger all-round workstation card. Its 20 GB GDDR6 memory provides more capacity for large datasets, and its lower 200 W TDP means simpler power delivery requirements, a single 8-pin connector, and a suggested 550 W PSU. The MI25's 300 W TDP and dual 8-pin connectors demand more from the host system. The benchmark data supports this: the A4500's 106.9% lead in Geekbench OpenCL is the only direct comparison recorded, and it is lopsided. The MI25's nearest rivals (Intel Arc A770, NVIDIA CMP 90HX, AMD Radeon Pro WX 8200, NVIDIA Quadro P6000) all score within 2% of it, indicating it remains competitive only with older or mid-range parts. The A4500, by contrast, sits among cards like the RTX A4500 Mobile, Instinct MI60, Quadro GP100, and Radeon PRO W7600, a higher tier overall. For users prioritizing modern compute features, ray tracing, and memory bandwidth, the A4500 is the clear winner; the MI25 may still serve specific FP16-centric compute roles, but its lack of RT cores, tensor cores, and display outputs limits its versatility.