Radeon Instinct MI455X vs RTX A40
Contents
Primary details
GPU architecture, market segment, value for money and other general parameters compared.
| Place in the ranking | not rated | not rated |
| Place by popularity | not in top-100 | not in top-100 |
| Architecture | Ampere (2020−2025) | CDNA 5.0 (2026) |
| GPU code name | GA102 | MI450 256CU |
| Market segment | Workstation | Workstation |
| Release date | 5 October 2020 (5 years ago) | 23 July 2026 (recently) |
Detailed specifications
General parameters such as number of shaders, GPU core base clock and boost clock speeds, manufacturing process, texturing and calculation speed. Real power consumption of some graphics cards can well exceed their nominal TDP, especially if overclocked.
| Pipelines / CUDA cores | 10752 | 32768 |
| Core clock speed | 1305 MHz | 1000 MHz |
| Boost clock speed | 1755 MHz | 2400 MHz |
| Number of transistors | 28,300 million | 320,000 million |
| Manufacturing process technology | 8 nm | 2 nm |
| Power consumption (TDP) | 300 Watt | 1400 Watt |
| Texture fill rate | 589.7 | 2,457.6 |
| Floating-point processing power | 37.74 TFLOPS | 157.3 TFLOPS |
| ROPs | 112 | no data |
| TMUs | 336 | 1024 |
| Tensor Cores | 336 | no data |
| Ray Tracing Cores | 84 | no data |
| L1 Cache | 10.5 MB | 8 MB |
| L2 Cache | 6 MB | 192 MB |
Form factor & compatibility
Information on compatibility with other computer components. Useful when choosing a future computer configuration or upgrading an existing one. For desktop graphics cards it's interface and bus (motherboard compatibility), additional power connectors (power supply compatibility).
| Interface | PCIe 4.0 x16 | PCIe 5.0 x16 |
| Length | 267 mm | no data |
| Width | 2-slot | EAM Module |
| Supplementary power connectors | 8-pin EPS | None |
VRAM capacity and type
Parameters of VRAM installed: its type, size, bus, clock and resulting bandwidth. Integrated GPUs have no dedicated video RAM and use a shared part of system RAM.
| Memory type | GDDR6 | HBM4 |
| Maximum RAM amount | 48 GB | 432 GB |
| Memory bus width | 384 Bit | 24576 Bit |
| Memory clock speed | 1812 MHz | 1900 MHz |
| Memory bandwidth | 695.8 GB/s | 23.3 TB/s |
| Resizable BAR | + | + |
Connectivity and outputs
This section shows the types and number of video connectors on each GPU. The data applies specifically to desktop reference models (for example, NVIDIA’s Founders Edition). OEM partners often modify both the number and types of ports. On notebook GPUs, video‐output options are determined by the laptop’s design rather than the graphics chip itself.
| Display Connectors | 3x DisplayPort | No outputs |
API and SDK support
List of supported 3D and general-purpose computing APIs, including their specific versions.
| DirectX | 12 Ultimate (12_2) | N/A |
| Shader Model | 6.5 | N/A |
| OpenGL | 4.6 | N/A |
| OpenCL | 2.0 | 3.0 |
| Vulkan | 1.2 | N/A |
| CUDA | 8.6 | - |
| DLSS | + | - |
Pros & cons summary
| Recency | 5 October 2020 | 23 July 2026 |
| Maximum RAM amount | 48 GB | 432 GB |
| Chip lithography | 8 nm | 2 nm |
| Power consumption (TDP) | 300 Watt | 1400 Watt |
RTX A40 has 367% lower power consumption.
Instinct MI455X, on the other hand, has an age advantage of 5 years, a 800% higher maximum VRAM amount, and a 300% more advanced lithography process.
We couldn't decide between RTX A40 and Radeon Instinct MI455X. We've got no test results to judge.
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