AMD Instinct MI355X vs AMD Radeon 780M Comparison

Head-to-Head Benchmarks

The comparison between the AMD Instinct MI355X and the AMD Radeon 780M is defined by their radically different roles in the computing ecosystem. The database records no direct head-to-head benchmark entries for these two products, which is expected given their distinct market positions. The MI355X is a datacenter compute accelerator with an average benchmark score of 0 and a percentile ranking of 50 among all GPUs, while the 780M is an integrated graphics processor with three recorded benchmark scores and a 61st percentile ranking.

The 780M delivers measurable results in the database: a 3DMark Steel Nomad DX12 score of 480, a Geekbench OpenCL score of 18602, and a Geekbench Vulkan score of 33683. Its average benchmark score sits at 17588. The MI355X has no recorded benchmark scores, and its average is listed as 0, which places it in an unusual percentile position of 50 despite having no test results. This suggests the database treats the MI355X as an unmeasured entry rather than a failed one, and its percentile reflects its classification within the accelerator segment rather than direct performance comparisons.

The 780M's nearest rivals in the database provide context for its measured performance. It sits within a tight cluster: the AMD Radeon Pro 560 scores 17551, which is 0.2% behind the 780M; the NVIDIA GeForce RTX 4060 scores 17639, which is 0.3% ahead; the AMD Radeon HD 7790 scores 17666, which is 0.4% ahead; and the AMD Radeon Pro 460 scores 17509, which is 0.5% behind. These deltas are remarkably small, all within half a percentage point, indicating that the 780M's average performance lands squarely in a competitive mid-range bracket for its class.

When comparing the two AMD products directly, the absence of shared benchmarks prevents a numerical head-to-head. The MI355X does not appear in the 780M's nearest rival list, and the head-to-head array in the database is empty. This means the analysis must rely on architectural specifications and production status rather than measured frame rates or compute scores. The data shows two completely different performance envelopes, but without shared tests, no direct score comparison is possible.

Where Each One Wins

The 780M wins in any scenario where measured benchmarks exist and where system integration matters. Its three recorded scores demonstrate capability in both compute-oriented OpenCL workloads and graphics-oriented Vulkan and DX12 tasks. The Geekbench Vulkan score of 33683 is more than double its OpenCL score of 18602, indicating strong graphics driver optimization. The 3DMark Steel Nomad DX12 score of 480, while numerically small, represents a modern DirectX 12 workload that the integrated GPU can complete. Its production status is listed as Active, and it was released on 2024-01-30, making it a current product with ongoing software support.

The MI355X wins in every category of raw compute capability, though the database records no benchmark scores to quantify this. Its shading units number 16384 versus the 780M's 768, a 21.3x difference in raw shader count. Texture mapping units stand at 1024 versus 48, a 21.3x difference. The MI355X's FP32 throughput is listed at 78.64 TFLOPS versus the 780M's 8.909 TFLOPS, an 8.8x difference in single-precision floating-point performance. The FP16 figures match the FP32 numbers for both products, with each listed as 1:1 ratio, so the same 8.8x gap applies to half-precision workloads.

The MI355X also wins on memory hierarchy. It has 288 GB of HBM3e memory with an 8192-bit bus and 8.19 TB/s bandwidth. The 780M uses System Shared memory, with bandwidth listed as System Dependent. The MI355X's memory subsystem is purpose-built for massive data movement, while the 780M depends entirely on the host system's memory configuration. In terms of texture rate, the MI355X delivers 2457.6 GTexel/s versus 139.2 GTexel/s for the 780M, a 17.7x difference. The MI355X's pixel rate is 0 MPixel/s because it has 0 ROPs, while the 780M has 32 ROPs and a pixel rate of 92.80 GPixel/s. This means the 780M can output rendered frames to a display, while the MI355X has no display outputs at all.

Architecture Differences

The architectural divide between these two AMD products is generational and fundamental. The MI355X uses CDNA 4.0 architecture, designed for compute acceleration, while the 780M uses RDNA 3.0, designed for graphics rendering and integrated use. The MI355X is built on a 3 nm process at TSMC, while the 780M uses a 4 nm process, also at TSMC. The MI355X's die size is 2380 mm² with 185,000 million transistors, giving a transistor density of 77.7 million per mm². The 780M's die is 178 mm² with 25,390 million transistors, giving a density of 142.6 million per mm². The 780M achieves higher transistor density despite the larger process node, indicating a more compact logic layout, while the MI355X's massive die accommodates its enormous shader array and memory controllers.

The MI355X has 16384 shading units but 0 ROPs, meaning it cannot perform traditional pixel output operations. The 780M has 768 shading units, 48 TMUs, 32 ROPs, and 12 ray tracing cores. The MI355X lists no ray tracing core count, and its API support is marked as N/A for DirectX, OpenGL, and Vulkan. The 780M supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. This API difference confirms that the MI355X is not a graphics card in the conventional sense; it is a compute accelerator that communicates through compute APIs or proprietary interfaces, while the 780M is a full graphics solution.

The memory architectures differ completely. The MI355X uses HBM3e with a 8192-bit bus and 8.19 TB/s bandwidth, a configuration built for high-bandwidth compute workloads. The 780M uses System Shared memory, meaning its bandwidth and capacity are determined by the host system's RAM, not by the GPU itself. The MI355X's clock speeds are 1000 MHz base and 2400 MHz boost, with memory clocked at 2000 MHz or 8 Gbps effective. The 780M runs at 800 MHz base and 2900 MHz boost, with no dedicated memory clock since it shares system memory. The 780M's higher boost clock reflects its graphics-oriented design, where higher clocks improve frame rendering, while the MI355X relies on massive parallelism rather than clock speed.

The instruction throughput differs in ratio but not in precision format. Both list FP16 as 1:1 with FP32, meaning neither has dedicated half-precision hardware that doubles throughput. This is notable because many compute accelerators double FP16 throughput, but the data shows both products treat FP16 as equal to FP32. The MI355X's FP32 of 78.64 TFLOPS is the headline compute figure, while the 780M's 8.909 TFLOPS is its graphics compute ceiling.

Specification Differences

The two products differ in nearly every specification field recorded in the database. The MI355X uses a chip labeled "MI350 256CU" while the 780M uses "Phoenix." The MI355X belongs to the Instinct (MIx) generation, the 780M to the Navi III IGP (Phoenix) generation. The MI355X has a 3 nm process node, the 780M has 4 nm. Transistor counts are 185,000 million versus 25,390 million. Die sizes are 2380 mm² versus 178 mm². Transistor densities are 77.7M per mm² versus 142.6M per mm².

Clock speeds: the MI355X runs at 1000 MHz base and 2400 MHz boost, the 780M at 800 MHz base and 2900 MHz boost. Memory: the MI355X has 288 GB of HBM3e with an 8192-bit bus and 8.19 TB/s bandwidth; the 780M uses System Shared memory with System Dependent bandwidth. Shading units: 16384 versus 768. TMUs: 1024 versus 48. ROPs: 0 versus 32. The 780M has 12 ray tracing cores; the MI355X lists none. Pixel rate: 0 MPixel/s versus 92.80 GPixel/s. Texture rate: 2457.6 GTexel/s versus 139.2 GTexel/s. FP32 and FP16: 78.64 TFLOPS versus 8.909 TFLOPS, both at 1:1 ratio.

Power and physical specifications also diverge. The MI355X has a TDP of 1400 W with a suggested PSU of 1800 W, while the 780M has a TDP of 15 W with no suggested PSU. The MI355X is an OAM Module with dimensions of 102 mm length and 165 mm width; the 780M is an IGP with no recorded dimensions. Both use "None" for power connectors, but the MI355X requires external power delivery through its module interface while the 780M draws power through the motherboard. The bus interface differs: PCIe 5.0 x16 for the MI355X versus PCIe 4.0 x8 for the 780M. Display outputs: the MI355X has none, the 780M has Motherboard Dependent outputs. API support: the MI355X lists N/A for all three APIs, the 780M lists DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4. Release dates: the MI355X launched on 2025-06-11, the 780M on 2024-01-30. The 780M has a production status of Active, while the MI355X has no status listed.

FAQ

Q: Why does the MI355X have a percentile rank of 50 when it has no benchmark scores?

A: The database records an average benchmark score of 0 for the MI355X, and its percentileVsAllGpus is 50. This likely reflects its classification within the accelerator category rather than measured performance, since no benchmark entries exist for it. The 780M, by contrast, has three scores and a 61st percentile.

Q: Can the MI355X render graphics to a display?

A: No. The MI355X has 0 ROPs, a pixel rate of 0 MPixel/s, and no display outputs. Its API support for DirectX, OpenGL, and Vulkan is listed as N/A. The 780M, with 32 ROPs, 92.80 GPixel/s pixel rate, and Motherboard Dependent display outputs, is the graphics-capable product.

Q: How much faster is the MI355X in raw compute?

A: The MI355X delivers 78.64 TFLOPS in both FP32 and FP16, while the 780M delivers 8.909 TFLOPS in both. This is an 8.8x difference. In texture rate, the MI355X reaches 2457.6 GTexel/s versus 139.2 GTexel/s, a 17.7x difference.

Q: Which product has more memory bandwidth?

A: The MI355X has 8.19 TB/s of bandwidth from 288 GB of HBM3e on an 8192-bit bus. The 780M uses System Shared memory with System Dependent bandwidth, so its bandwidth cannot be compared directly and depends entirely on the host system.

Q: What is the transistor density difference?

A: Despite using a larger 4 nm node, the 780M has a higher transistor density at 142.6 million per mm². The MI355X, on a 3 nm node, has 77.7 million per mm². The MI355X compensates with a much larger die: 2380 mm² versus 178 mm².

Q: Are these products in the same performance class?

A: No. The database's nearest rival list for the 780M includes the AMD Radeon Pro 560, NVIDIA GeForce RTX 4060, AMD Radeon HD 7790, and AMD Radeon Pro 460, all within 0.5% of its average score of 17588. The MI355X has no rivals listed and no comparable benchmarks, placing it in a separate compute accelerator category.

The Verdict

The data indicates two products with no overlap in purpose. The AMD Radeon 780M is an active integrated graphics processor with measured scores, a 61st percentile rank, and support for modern graphics APIs including DirectX 12 Ultimate and Vulkan 1.4. Its nearest rivals are all within half a percentage point of its average score, showing it sits in a competitive mid-range position for integrated graphics. The 780M is the only choice for systems requiring display output, ray tracing support with 12 dedicated cores, and a low 15 W TDP that requires no separate power delivery.

The AMD Instinct MI355X is a datacenter compute accelerator with no recorded benchmarks, no display outputs, no graphics API support, and a 1400 W TDP. Its advantages are purely architectural: 16384 shading units, 288 GB of HBM3e memory with 8.19 TB/s bandwidth, and 78.64 TFLOPS of FP32 compute. It uses PCIe 5.0 x16 and comes as an OAM Module with a suggested 1800 W PSU. The 780M uses PCIe 4.0 x8 and draws 15 W.

For any workload involving rendering frames, running graphics APIs, or operating within a standard desktop or laptop power envelope, the 780M is the only viable option from this comparison. For any workload involving massive parallel compute, large memory footprints, or high-bandwidth data movement, the MI355X's specifications indicate it is built for that role, though the database lacks measured scores to confirm its absolute performance. The 780M's average benchmark score of 17588 and its tight rival cluster confirm it performs competitively in its class. The MI355X's 0 average score and empty benchmark list mean its real-world performance remains unquantified in the database, but its architectural specifications point to a compute-focused design with no graphics capability whatsoever.