AMD Instinct MI355X vs AMD Radeon 8040S Comparison

Head-to-Head Benchmarks

The comparison between the AMD Instinct MI355X and the AMD Radeon 8040S is fundamentally lopsided, as the database records no head-to-head benchmark entries for these two products. The Instinct MI355X, an accelerator built on the CDNA 4.0 architecture with a 3 nm process, is designed for compute workloads, while the Radeon 8040S, an integrated graphics processor based on RDNA 3.5, targets mobile or embedded systems. The absence of shared benchmark scores means direct numerical comparisons are unavailable.

However, the Radeon 8040S does have recorded benchmark data. Its PassMark DirectX 9 score is 134, DirectX 10 is 48, DirectX 11 is 80, and DirectX 12 is 47. The G2D score is 1052, while the G3D score reaches 10578. The GPU compute score is 5138. The average benchmark score across these tests is 2440. This places the Radeon 8040S at the 17th percentile of all GPUs in the database, indicating it sits in the lower performance tier.

The Instinct MI355X, by contrast, has no benchmark scores recorded and no nearest rivals listed. Its percentile rank is 50, but this is based on zero measured results, so it reflects the database's default position rather than a tested outcome. The FP32 compute rating for the MI355X is 78.64 TFLOPS, while the Radeon 8040S delivers 5.734 TFLOPS. That is a substantial gap, but these figures come from specification sheets, not from benchmark runs.

The Radeon 8040S's nearest rivals illustrate its competitive position. The NVIDIA GeForce 710M has an average score of 2433, which is 0.3% behind the 8040S. The Intel HD Graphics 610 scores 2425, 0.6% behind. The NVIDIA GeForce GT 710M scores 2422, 0.7% behind. The AMD Radeon RX 7400 scores 2467, which is 1.1% ahead of the 8040S. These deltas are small, showing that the 8040S sits in a narrow band of low-end GPUs where minor score differences separate the products.

The Instinct MI355X has no such comparisons. Without benchmark entries, the database cannot compute win counts or delta percentages for it. The winsA and winsB fields are both zero, confirming that no measured head-to-head contests exist. This means the analysis must rely on architectural and specification differences rather than performance scores.

Where Each One Wins

The Radeon 8040S wins in scenarios where its integrated nature and low power draw are advantageous. It has a TDP of 55 W, making it suitable for portable devices where power consumption is a constraint. It supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, which means it can handle modern graphics APIs in consumer applications. Its display outputs are portable device dependent, aligning with mobile use cases. The Radeon 8040S also has 16 ray tracing cores, enabling hardware-accelerated ray tracing in supported games, a feature the Instinct MI355X lacks entirely.

The Instinct MI355X wins in compute-heavy environments. Its 288 GB of HBM3e memory with a 8192-bit bus width delivers 8.19 TB/s of bandwidth, which is orders of magnitude beyond what a system-shared memory setup can offer. The Radeon 8040S relies on system shared memory, with bandwidth described as system dependent, meaning it cannot match dedicated high-bandwidth storage. The MI355X's 16384 shading units and 1024 texture mapping units process massive parallel workloads, with a texture rate of 2,457.6 GTexel/s compared to the 8040S's 179.2 GTexel/s.

The MI355X also wins in raw compute throughput. Its FP16 performance is 78.64 TFLOPS (1:1 ratio), identical to its FP32 figure, which is typical for CDNA accelerators designed for AI and scientific workloads. The Radeon 8040S offers 5.734 TFLOPS for both FP16 and FP32, also at a 1:1 ratio, but at a much lower magnitude. For tasks like large-scale matrix operations or neural network training, the MI355X is the clear choice. For gaming or lightweight graphics on a portable device, the Radeon 8040S is the only viable option, as the MI355X has no display outputs at all.

Architecture Differences

The two GPUs come from different architectural lineages. The Instinct MI355X uses CDNA 4.0, a compute-optimized design, while the Radeon 8040S uses RDNA 3.5, a graphics-oriented architecture. The manufacturing processes differ: the MI355X is built on a 3 nm node at TSMC, while the 8040S uses a 4 nm node, also at TSMC. The MI355X has a die size of 2380 mm² with 185,000 million transistors, yielding a density of 77.7 million transistors per square millimeter. The 8040S has a die size of 308 mm², with transistor count listed as unknown.

The memory subsystems are fundamentally different. The MI355X uses HBM3e with 288 GB capacity, an 8192-bit bus, and 8.19 TB/s bandwidth. The 8040S uses system shared memory, meaning its capacity, bus width, and bandwidth are all dependent on the host system. The MI355X has a memory clock of 2000 MHz, translating to 8 Gbps effective, while the 8040S has no dedicated memory clock.

The core configurations diverge sharply. The MI355X has 16384 shading units, 1024 TMUs, and zero ROPs, with a pixel rate of 0 MPixel/s, confirming it is not designed for rasterization. The 8040S has 1024 shading units, 64 TMUs, and 32 ROPs, with a pixel rate of 89.60 GPixel/s. The 8040S includes 16 ray tracing cores, while the MI355X has none listed. The MI355X's base clock is 1000 MHz with a boost of 2400 MHz, whereas the 8040S has a base of 1295 MHz and a boost of 2800 MHz, showing higher clock speeds but far fewer execution units.

Power and form factor differences are stark. The MI355X has a TDP of 1400 W and uses an OAM module slot, with no power connectors listed and a suggested PSU of 1800 W. The 8040S has a TDP of 55 W and is an IGP (integrated graphics processor), with no power connectors and no suggested PSU. The MI355X measures 102 mm in length and 165 mm in width, while the 8040S has no recorded dimensions. The MI355X has no display outputs, while the 8040S's outputs are portable device dependent. Both use PCIe 5.0 x16 interfaces.

The MI355X supports no DirectX, OpenGL, or Vulkan APIs, reinforcing its role as a compute accelerator rather than a graphics card. The 8040S supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, making it fully capable of modern graphics rendering. The release dates differ: the MI355X was released on June 11, 2025, while the 8040S came earlier on January 5, 2025. The MI355X's predecessor is listed as Radeon Instinct, and the 8040S's predecessor is Polaris Mobile.

FAQ

Q: Which GPU has higher FP32 compute performance?

A: The AMD Instinct MI355X delivers 78.64 TFLOPS of FP32 performance, compared to the AMD Radeon 8040S's 5.734 TFLOPS. The MI355X is over 13 times faster in this metric.

Q: Can the Instinct MI355X output to a display?

A: No. The MI355X has no display outputs listed in its specifications. The Radeon 8040S, by contrast, has display outputs that are portable device dependent.

Q: What is the memory configuration of each GPU?

A: The Instinct MI355X uses 288 GB of HBM3e memory with an 8192-bit bus and bandwidth of 8.19 TB/s. The Radeon 8040S uses system shared memory, with its capacity, bus width, and bandwidth all being system dependent.

Q: Which GPU supports ray tracing?

A: The Radeon 8040S includes 16 ray tracing cores. The Instinct MI355X has no ray tracing cores listed, consistent with its compute-focused CDNA 4.0 architecture.

Q: How do their power requirements compare?

A: The Instinct MI355X has a TDP of 1400 W and a suggested PSU of 1800 W. The Radeon 8040S has a TDP of 55 W and no suggested PSU listed.

Q: What is the Radeon 8040S's benchmark standing relative to its nearest rivals?

A: The Radeon 8040S has an average benchmark score of 2440. It is 0.3% ahead of the NVIDIA GeForce 710M, 0.6% ahead of the Intel HD Graphics 610, and 0.7% ahead of the NVIDIA GeForce GT 710M. It trails the AMD Radeon RX 7400 by 1.1%.

The Verdict

The data indicates that these two GPUs serve entirely different purposes. The AMD Instinct MI355X is a compute accelerator with massive memory bandwidth, a 1400 W power envelope, and no graphics output. It is built for data center or high-performance computing tasks where FP32 and FP16 throughput of 78.64 TFLOPS is necessary. The AMD Radeon 8040S is an integrated graphics solution with a 55 W TDP, ray tracing support, and full modern graphics API compatibility, designed for portable devices.

Users requiring a GPU for gaming, consumer graphics, or mobile computing should select the Radeon 8040S, as it supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, and has active production status. The MI355X cannot render to any display and lacks all graphics APIs, making it unsuitable for such tasks. Conversely, users needing high-bandwidth compute for AI, scientific simulation, or large-scale data processing should choose the Instinct MI355X, as its 288 GB HBM3e memory and 8.19 TB/s bandwidth dwarf the system shared memory approach of the 8040S.

The benchmark records show that the Radeon 8040S occupies a low-end position at the 17th percentile, narrowly ahead of several older mobile GPUs but behind the RX 7400. The Instinct MI355X has no recorded benchmarks, so its percentile rank of 50 is unverified. The architectural evidence, however, shows a clear performance hierarchy in compute tasks, with the MI355X's shading unit count (16384 vs 1024), texture rate (2,457.6 GTexel/s vs 179.2 GTexel/s), and memory bandwidth (8.19 TB/s vs system dependent) all indicating vastly superior throughput. The choice between them is not a matter of preference but of workload: compute versus graphics, data center versus portable device.