AMD Instinct MI355X vs AMD Radeon RX 7800M Comparison

Head-to-Head Benchmarks

The database contains no directly paired benchmark results for the AMD Instinct MI355X and the AMD Radeon RX 7800M. The Instinct MI355X has no recorded benchmark scores, an average benchmark score of 0, and sits at the 50th percentile among all GPUs. In contrast, the Radeon RX 7800M has ten recorded benchmark scores, an average benchmark score of 27883, and sits at the 73rd percentile. This absence of overlapping data means the head-to-head comparison relies entirely on architectural specifications and the RX 7800M's measured performance relative to its nearest rivals.

The RX 7800M delivers a passmark_g3d score of 17613, a passmark_gpu_compute score of 9342, a geekbench_opencl score of 120778, and a geekbench_vulkan score of 126668. Its 3dmark_steel_nomad_dx12 score is 2994. The passmark DirectX scores are 99 for DirectX 10, 176 for DirectX 11, 89 for DirectX 12, and 174 for DirectX 9, with a passmark_g2d score of 892. Against its nearest rivals, the RX 7800M is 0.2% ahead of the AMD Radeon Pro Vega 20, 0.3% behind the AMD Radeon Pro W5500X, 0.5% behind the NVIDIA GeForce GTX 980 Ti, and 0.8% behind the AMD FirePro S7150. These deltas are all within one percentage point, indicating that the RX 7800M performs in a tight cluster around these four cards.

The Instinct MI355X, by contrast, has no measured scores to compare. Its percentile ranking of 50 is the median placement for all GPUs in the database, but with zero benchmark entries, this percentile reflects the absence of data rather than a performance verdict. The RX 7800M's 73rd percentile places it above the median, and its average score of 27883 is a concrete figure derived from actual runs. The difference in data availability is the first major finding: one product has a full benchmark profile, the other has none.

Where Each One Wins

The RX 7800M wins on every measurable benchmark category because it is the only product with recorded scores. Its passmark_g3d score of 17613 indicates strong general 3D rendering capability, and its geekbench_vulkan score of 126668 shows robust cross-platform graphics compute. The geekbench_opencl score of 120778 confirms competitive OpenCL throughput. The passmark_gpu_compute score of 9342 reflects compute-oriented workloads, while the DirectX 11 score of 176 is the highest among its DirectX results, suggesting favorable performance in legacy DirectX 11 titles. The DirectX 9 score of 174 is nearly identical, and the DirectX 10 score of 99 is notably lower, indicating a larger drop in that generation's feature set. The DirectX 12 score of 89 is the lowest DirectX figure, which may point to weaker optimization in modern API workloads relative to its other results.

The Instinct MI355X cannot win any benchmark category because no scores exist for it. Its specifications, however, indicate a different class of hardware. The MI355X uses a 3 nm process node from TSMC, has 185,000 million transistors on a 2380 mm² die, and features an 8192-bit memory bus with 288 GB of HBM3e memory delivering 8.19 TB/s of bandwidth. The RX 7800M uses a 5 nm process node, has 28,100 million transistors on a 346 mm² die, and features a 192-bit bus with 12 GB of GDDR6 memory delivering 432.0 GB/s. The MI355X has 16384 shading units, 1024 texture mapping units, and zero ROPs, while the RX 7800M has 3840 shading units, 240 TMUs, and 96 ROPs. The MI355X's texture rate is 2,457.6 GTexel/s versus the RX 7800M's 560.4 GTexel/s. The MI355X's FP32 compute is 78.64 TFLOPS, and its FP16 is also 78.64 TFLOPS at a 1:1 ratio, while the RX 7800M delivers 35.87 TFLOPS in both FP32 and FP16 at a 1:1 ratio.

The RX 7800M wins on pixel rate with 224.2 GPixel/s, while the MI355X has a pixel rate of 0 MPixel/s due to its lack of ROPs. The MI355X wins on raw compute throughput, texture rate, memory capacity, memory bandwidth, and transistor count. The RX 7800M wins on having a functional pixel pipeline, a lower power draw of 180 W versus 1400 W, and a complete set of API support including DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4. The MI355X lists no API support for DirectX, OpenGL, or Vulkan, marking it as a compute-oriented accelerator rather than a graphics renderer.

The Verdict

The data indicates two fundamentally different products serving different purposes. The AMD Instinct MI355X is an OAM module with no display outputs, no ROPs, and no graphics API support, built for high-throughput compute workloads. Its 1400 W TDP, 288 GB HBM3e memory, and 78.64 TFLOPS FP32 compute position it as a data center accelerator. The AMD Radeon RX 7800M is an IGP (integrated graphics processor) for mobile devices, with 180 W TDP, 12 GB GDDR6 memory, 35.87 TFLOPS FP32 compute, 96 ROPs, and full graphics API support including DirectX 12 Ultimate and Vulkan 1.4. The RX 7800M has an active production status, while the MI355X has no recorded production status.

For a user selecting a GPU for measured, benchmarkable graphics performance, the RX 7800M is the only option with data. Its average benchmark score of 27883 and 73rd percentile ranking come from real runs. For a user selecting a GPU for compute density, memory bandwidth, and raw FP32 throughput, the MI355X's specifications are superior in every compute metric, but no benchmark data exists to validate its real-world performance. The RX 7800M's nearest rivals all score within 0.8% of its average, meaning its performance class is well established. The MI355X has no rivals listed, so its relative standing cannot be assessed from the database.

The verdict is straightforward: the RX 7800M is the benchmarked graphics solution with a complete feature set, and the MI355X is an unbenchmarked compute accelerator with far higher theoretical throughput. Neither product replaces the other.

FAQ

Q: What is the average benchmark score for the AMD Radeon RX 7800M?

A: The RX 7800M has an average benchmark score of 27883, based on ten recorded benchmark tests.

Q: Does the AMD Instinct MI355X have any benchmark scores?

A: No, the MI355X has an empty benchmarks array, an average benchmark score of 0, and no nearest rivals listed.

Q: What is the memory bandwidth difference between the two GPUs?

A: The MI355X has 8.19 TB/s of bandwidth from 288 GB of HBM3e on an 8192-bit bus, while the RX 7800M has 432.0 GB/s from 12 GB of GDDR6 on a 192-bit bus.

Q: Which GPU has a higher FP32 compute rating?

A: The MI355X has 78.64 TFLOPS FP32, which is more than double the RX 7800M's 35.87 TFLOPS FP32.

Q: What is the pixel rate for each GPU?

A: The RX 7800M has a pixel rate of 224.2 GPixel/s, while the MI355X has a pixel rate of 0 MPixel/s because it has zero ROPs.

Q: What API support does the MI355X have?

A: The MI355X lists DirectX as N/A, OpenGL as N/A, and Vulkan as N/A, meaning no graphics API support is recorded.

Architecture Differences

The MI355X uses the CDNA 4.0 architecture on the MI350 256CU chip, while the RX 7800M uses the RDNA 3.0 architecture on the Navi 32 chip. These are different architecture families: CDNA is compute-focused, and RDNA is graphics-focused. The MI355X has 16384 shading units and 1024 TMUs but zero ROPs, confirming that it is not designed for rasterization. The RX 7800M has 3840 shading units, 240 TMUs, and 96 ROPs, enabling full graphics output. The RX 7800M also has 60 ray tracing cores, while the MI355X has no ray tracing cores listed.

The MI355X is built on a 3 nm process node from TSMC with 185,000 million transistors on a 2380 mm² die, giving a transistor density of 77.7M per mm². The RX 7800M is built on a 5 nm process node from TSMC with 28,100 million transistors on a 346 mm² die, giving a transistor density of 81.2M per mm². The RX 7800M has a higher transistor density despite the older node. The MI355X's memory is HBM3e, while the RX 7800M uses GDDR6. The MI355X has no display outputs, while the RX 7800M's display outputs are portable device dependent.

The MI355X supports PCIe 5.0 x16, while the RX 7800M supports PCIe 4.0 x16. The MI355X has no power connectors and a suggested PSU of 1800 W, while the RX 7800M also has no power connectors but no suggested PSU is listed. The MI355X has no API support, while the RX 7800M supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4.

Specification Differences

The following fields differ between the two GPUs:

• Chip: MI350 256CU for the MI355X versus Navi 32 for the RX 7800M.
• Architecture: CDNA 4.0 versus RDNA 3.0.
• Codename: None for the MI355X versus Wheat Nas for the RX 7800M.
• Generation: Instinct (MIx) versus Navi Mobile (RX 7000M).
• Process Node: 3 nm versus 5 nm.
• Transistors: 185,000 million versus 28,100 million.
• Die Size: 2380 mm² versus 346 mm².
• Transistor Density: 77.7M / mm² versus 81.2M / mm².
• Base Clock: 1000 MHz versus 1295 MHz.
• Boost Clock: 2400 MHz versus 2335 MHz.
• Game Clock: None versus 2145 MHz.
• Memory Clock: 2000 MHz 8 Gbps effective versus 2250 MHz 18 Gbps effective.
• Memory Size: 288 GB versus 12 GB.
• Memory Type: HBM3e versus GDDR6.
• Memory Bus Width: 8192 bit versus 192 bit.
• Memory Bandwidth: 8.19 TB/s versus 432.0 GB/s.
• Shading Units: 16384 versus 3840.
• TMUs: 1024 versus 240.
• ROPs: 0 versus 96.
• Ray Tracing Cores: None versus 60.
• Pixel Rate: 0 MPixel/s versus 224.2 GPixel/s.
• Texture Rate: 2,457.6 GTexel/s versus 560.4 GTexel/s.
• FP32: 78.64 TFLOPS versus 35.87 TFLOPS.
• FP16: 78.64 TFLOPS (1:1) versus 35.87 TFLOPS (1:1).
• TDP: 1400 W versus 180 W.
• Slot Width: OAM Module versus IGP.
• Suggested PSU: 1800 W versus none listed.
• Bus Interface: PCIe 5.0 x16 versus PCIe 4.0 x16.
• Display Outputs: No outputs versus Portable Device Dependent.
• DirectX: N/A versus 12 Ultimate (12_2).
• OpenGL: N/A versus 4.6.
• Vulkan: N/A versus 1.4.
• Dimensions: Length 102 mm and width 165 mm for the MI355X versus no dimensions for the RX 7800M.
• Production Status: None versus Active.
• Release Date: 2025-06-11 versus 2024-09-10.
• Predecessor: Radeon Instinct versus Polaris Mobile.
• Percentile: 50 versus 73.
• Average Benchmark Score: 0 versus 27883.
• Benchmark Count: 0 versus 10.