AMD Instinct MI455X vs AMD Radeon 8065S Comparison

AMD Instinct MI455X and AMD Radeon 8065S occupy opposite ends of the GPU spectrum, one built for massive compute workloads and the other for compact mobile graphics. The database shows no direct head-to-head benchmark runs between these two parts, so the comparison relies on their recorded specifications and architectural parameters. The MI455X targets rack-scale acceleration with a 2 nm process, while the 8065S is an integrated graphics processor for portable devices. Both carry the AMD name, but their design goals diverge sharply.

Head-to-Head Benchmarks

The recorded data contains no overlapping benchmark scores for the AMD Instinct MI455X and the AMD Radeon 8065S. The MI455X lists an average benchmark score of 0 with no entries in its benchmark array, and the 8065S similarly shows an average benchmark score of 0 with an empty benchmark list. Without shared test results, the database cannot produce a direct performance comparison. The percentile ranking for both GPUs sits at 50, which places each at the median of all recorded GPUs, but this figure does not reflect any measured contest between them.

What the data does provide is a clear picture of theoretical compute capacity. The MI455X delivers 157.3 TFLOPS of FP32 performance and the same 157.3 TFLOPS for FP16, running both at a 1:1 ratio. The Radeon 8065S manages 15.36 TFLOPS of FP32 and 15.36 TFLOPS of FP16, also at a 1:1 ratio. The MI455X therefore holds a 10.2x advantage in raw FP32 throughput, a gap that dwarfs any other difference between the two cards. Texture rate tells a similar story: the MI455X reaches 2,457.6 GTexel/s against 480.0 GTexel/s for the 8065S, a 5.1x margin. Pixel rate flips the comparison entirely, as the MI455X is recorded at 0 MPixel/s while the 8065S produces 192.0 GPixel/s, because the MI455X has no raster output units and no display outputs.

Memory bandwidth favors the MI455X overwhelmingly. The Instinct card uses 432 GB of HBM4 memory on a 24576-bit bus, achieving 23.3 TB/s of bandwidth. The 8065S relies on system shared memory with bandwidth listed as system dependent, meaning its throughput varies with the host platform. The MI455X also operates with far more shading units: 32768 versus 2560, a 12.8x difference. Texture mapping units number 1024 on the MI455X compared to 160 on the 8065S, a 6.4x gap. The 8065S counters with 64 ROPs and 40 ray accelerators, while the MI455X lists no RT cores and zero ROPs. Clock speeds favor the smaller chip: the 8065S boosts to 3000 MHz from a 1295 MHz base, while the MI455X boosts to 2400 MHz from a 1000 MHz base.

Where Each One Wins

The data points to distinct use cases for each GPU. The MI455X wins decisively in compute-heavy workloads that scale with FP32 or FP16 throughput. Its 157.3 TFLOPS in both precisions suits dense matrix operations, and the 23.3 TB/s memory bandwidth feeds that compute engine without bottlenecking. The 432 GB HBM4 pool provides capacity for datasets that would never fit in the shared memory of a mobile part. The 2 nm process node and 320,000 million transistors on a 2990 mm² die indicate a device engineered for sustained throughput in server environments, not for interactive graphics.

The Radeon 8065S wins in scenarios that require rasterization and ray tracing. Its 64 ROPs deliver 192.0 GPixel/s, a figure the MI455X cannot match because it has no ROPs at all. The 40 RT cores give the 8065S hardware acceleration for ray-traced effects, a feature entirely absent from the MI455X. The 8065S also supports a full modern graphics API stack: DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The MI455X lists no API support, with DirectX, OpenGL, and Vulkan all marked as N/A. For any workload that ends in a display output, the 8065S is the only viable option, since the MI455X has no display outputs and the 8065S outputs are portable device dependent.

Power consumption separates the two further. The MI455X carries a TDP of 2300 W and a suggested PSU of 2700 W, which anchors it to a server rack with dedicated power delivery. The 8065S draws 55 W and requires no suggested PSU, fitting into laptops or other portable devices where power is at a premium. The bus interface differs as well: the MI455X uses PCIe 6.0 x16, while the 8065S uses PCIe 5.0 x16. The MI455X is an EAM Module with no power connectors, while the 8065S is an IGP with no power connectors either, but the latter's modest power draw makes integration into a mobile platform straightforward.

Architecture Differences

The two GPUs come from completely different architectural lineages. The MI455X is built on CDNA 5.0, AMD's compute-focused architecture, and belongs to the Instinct (MIx) generation. Its chip is labeled MI450 256CU, indicating 256 compute units. The 8065S uses RDNA 3.5, a graphics-oriented architecture, and is part of the Navi Mobile (RX 8000M) generation. Its chip is called Gorgon Halo. The process nodes reflect their roles: the MI455X uses a 2 nm process from TSMC, while the 8065S uses a 4 nm process, also from TSMC. The MI455X packs 320,000 million transistors into a 2990 mm² die, yielding a transistor density of 107.0M per mm². The 8065S has an unknown transistor count and a 308 mm² die, with no density figure recorded.

Memory architecture could not differ more. The MI455X uses 432 GB of HBM4 with a 24576-bit bus and 23.3 TB/s bandwidth, a configuration built for massive parallel access. The 8065S uses system shared memory for everything: capacity, type, bus width, and bandwidth are all listed as system shared or system dependent. This means the 8065S borrows from the host CPU's memory pool, which introduces variability based on the platform. Clock behavior also differs: the MI455X runs a 1000 MHz base and 2400 MHz boost with memory at 1900 MHz (7.6 Gbps effective), while the 8065S runs a 1295 MHz base and 3000 MHz boost with no separate memory clock because it shares system memory.

Feature sets diverge in ways that matter for real workloads. The MI455X has no RT cores, no ROPs, and no display outputs. The 8065S has 40 RT cores, 64 ROPs, and portable device dependent display outputs. The MI455X has no API support recorded, while the 8065S supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The MI455X's 1024 TMUs and 32768 shading units serve compute shaders and general math, but the 8065S's 160 TMUs and 2560 shading units serve the graphics pipeline that ends at a screen. The production status also differs: the 8065S is listed as active, while the MI455X has no production status recorded. Release dates place the 8065S first at the end of 2025, with the MI455X following in mid-2026. The MI455X's predecessor is Radeon Instinct, and the 8065S's predecessor is Polaris Mobile, showing that each card continues a distinct product line.

FAQ

Q: Which GPU has higher FP32 performance?

A: The AMD Instinct MI455X delivers 157.3 TFLOPS of FP32, compared to 15.36 TFLOPS for the AMD Radeon 8065S, a 10.2x advantage.

Q: Can the MI455X output video to a display?

A: No. The MI455X lists no display outputs and no API support, with pixel rate recorded at 0 MPixel/s. The Radeon 8065S provides portable device dependent display outputs.

Q: What memory does each GPU use?

A: The MI455X uses 432 GB of HBM4 on a 24576-bit bus with 23.3 TB/s bandwidth. The 8065S uses system shared memory with system dependent bandwidth.

Q: Does the Radeon 8065S support ray tracing?

A: Yes. The 8065S includes 40 RT cores, while the MI455X has no RT cores listed.

Q: What is the power draw difference?

A: The MI455X has a TDP of 2300 W with a suggested PSU of 2700 W. The 8065S has a TDP of 55 W and no suggested PSU.

Q: Which GPU was released first?

A: The Radeon 8065S has a release date of 2025-12-31, while the Instinct MI455X has a release date of 2026-07-22.

Specification Differences

The two GPUs differ on nearly every recorded specification. The MI455X uses the MI450 256CU chip with CDNA 5.0 architecture, while the 8065S uses the Gorgon Halo chip with RDNA 3.5. Process nodes are 2 nm versus 4 nm, both from TSMC. Transistor count is 320,000 million for the MI455X versus unknown for the 8065S, and die size is 2990 mm² versus 308 mm². Transistor density is 107.0M per mm² for the MI455X, with no density recorded for the 8065S.

Clock speeds differ across the board. The MI455X has a 1000 MHz base and 2400 MHz boost, while the 8065S runs at 1295 MHz base and 3000 MHz boost. Memory clocks only apply to the MI455X at 1900 MHz (7.6 Gbps effective), since the 8065S uses system shared memory. Memory capacity, type, bus width, and bandwidth all differ: 432 GB HBM4 on 24576-bit with 23.3 TB/s for the MI455X, versus system shared memory with system dependent bandwidth for the 8065S.

Compute units diverge in scale. The MI455X has 32768 shading units, 1024 TMUs, and 0 ROPs. The 8065S has 2560 shading units, 160 TMUs, and 64 ROPs. The MI455X has no RT cores, while the 8065S has 40. Pixel rate is 0 MPixel/s for the MI455X and 192.0 GPixel/s for the 8065S. Texture rate is 2,457.6 GTexel/s for the MI455X and 480.0 GTexel/s for the 8065S. FP32 and FP16 are both 157.3 TFLOPS for the MI455X and 15.36 TFLOPS for the 8065S.

Power and form factor separate them completely. The MI455X has a 2300 W TDP and 2700 W suggested PSU, while the 8065S has a 55 W TDP and no suggested PSU. The MI455X is an EAM Module, the 8065S is an IGP. Both use no power connectors. Bus interfaces are PCIe 6.0 x16 for the MI455X and PCIe 5.0 x16 for the 8065S. Display outputs are none for the MI455X and portable device dependent for the 8065S. API support is N/A for the MI455X, while the 8065S supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. Production status is unrecorded for the MI455X and active for the 8065S. Release dates are 2026-07-22 for the MI455X and 2025-12-31 for the 8065S. Predecessors are Radeon Instinct for the MI455X and Polaris Mobile for the 8065S.

The Verdict

The database describes two GPUs with almost no overlap in purpose. The AMD Instinct MI455X is a compute accelerator with 157.3 TFLOPS of FP32, 432 GB of HBM4, and 23.3 TB/s of bandwidth, but it lacks display outputs, ROPs, and graphics API support. Its 2300 W TDP and EAM Module form factor place it firmly in server infrastructure. The AMD Radeon 8065S is a mobile integrated GPU with 15.36 TFLOPS, 64 ROPs, 40 RT cores, and full DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 support, all within a 55 W envelope.

Anyone selecting between them should start with the workload. If the task is dense compute that can use FP32 or FP16 throughput, the MI455X offers 10.2x the raw math performance and a memory subsystem that scales to 23.3 TB/s. If the task involves rasterization, ray tracing, or any form of display output, the 8065S is the only option that supports it. The MI455X cannot render frames, and the 8065S cannot approach the MI455X's compute density. The recorded data shows no benchmark overlap, but the specification gap makes the intended use case clear. The MI455X belongs in a rack, the 8065S belongs in a portable device, and the choice depends entirely on which environment the workload targets.