AMD Instinct MI308X vs AMD Radeon RX 6450M Comparison

Head-to-Head Benchmarks

The database contains no recorded head-to-head benchmark comparisons between the AMD Instinct MI308X and the AMD Radeon RX 6450M. Both parts also have no individual benchmark scores recorded, and each sits at the 50th percentile among all GPUs in the database with an average benchmark score of zero. The absence of measured data means the comparison must rely entirely on architectural specifications and the theoretical throughput figures provided for each product.

The raw compute figures reveal an enormous gulf. The Instinct MI308X delivers 81.72 TFLOPS of FP32 performance, while the RX 6450M delivers 3.779 TFLOPS. That places the MI308X roughly 21.6 times higher in single-precision throughput. In FP16, the MI308X again posts 81.72 TFLOPS on a 1:1 ratio, while the RX 6450M achieves 7.557 TFLOPS on a 2:1 ratio. The MI308X leads by a factor of about 10.8 in FP16, though the RX 6450M's 2:1 rate means it can dedicate double the clock cycles to each FP16 operation relative to its FP32 rate, a design choice that narrows the raw gap only slightly.

Memory capacity and bandwidth follow the same trajectory. The MI308X carries 192 GB of HBM3 on an 8192-bit bus, yielding 5.32 TB/s of bandwidth. The RX 6450M has 4 GB of GDDR6 on a 64-bit bus, producing 128.0 GB/s. The MI308X offers 48 times the memory capacity and roughly 41.6 times the bandwidth. These are not incremental differences; they represent entirely different performance classes.

Texture and pixel processing tell a similar story. The MI308X reaches 2,553.6 GTexel/s of texture rate, while the RX 6450M reaches 118.1 GTexel/s. The MI308X leads by over 21.6 times. The MI308X reports a pixel rate of 0 MPixel/s, as it has no ROPs configured (0 ROPs in the specification), which is consistent with a compute-oriented accelerator that does not drive display output. The RX 6450M, by contrast, has 32 ROPs and a pixel rate of 78.72 GPixel/s, making it the only one of the two with any rasterization output capability.

The Verdict

The data indicates these two GPUs target completely different workloads, and the lack of shared benchmark data means no direct performance comparison can be drawn from measured results. The Instinct MI308X is an accelerator with 19,456 shading units, 1,216 TMUs, and no ROPs, built for high-throughput compute in server environments. The RX 6450M is a mobile graphics processor with 768 shading units, 48 TMUs, and 32 ROPs, designed for rendering and display output in portable devices.

From the specification sheet alone, the MI308X should be selected for any workload that demands massive FP32 or FP16 compute, enormous memory capacity, or extreme memory bandwidth. Its 192 GB HBM3 pool and 5.32 TB/s bandwidth are an order of magnitude beyond what the RX 6450M can provide. The RX 6450M, meanwhile, is the only one of the two with display outputs (listed as portable device dependent), a full DirectX 12 Ultimate feature set, OpenGL 4.6, and Vulkan 1.4 support. The MI308X lists no supported graphics APIs and no display outputs.

The MI308X uses a 5 nm TSMC process with 153,000 million transistors on a 1017 mm² die, while the RX 6450M uses a 6 nm TSMC process with 5,400 million transistors on a 107 mm² die. The MI308X has a transistor density of 150.4M per mm², while the RX 6450M has 50.5M per mm². The MI308X consumes up to 750 W and requires a suggested PSU of 1150 W, while the RX 6450M consumes 50 W. Neither card has external power connectors, and the MI308X is an OAM module while the RX 6450M is an IGP.

Where Each One Wins

The Instinct MI308X wins decisively in every compute-heavy category. Its FP32 throughput of 81.72 TFLOPS versus 3.779 TFLOPS makes it the clear choice for scientific simulation, AI training, and large-scale data processing where single-precision math dominates. Its FP16 capability matches its FP32 rate at 81.72 TFLOPS, which suits mixed-precision machine learning workloads that do not rely on dedicated tensor cores. The MI308X also has no tensor core count listed, so FP16 work must run on the shading units themselves, but the raw throughput is still over ten times that of the RX 6450M.

The MI308X also wins on memory. Its 192 GB capacity supports models and datasets that would never fit in the RX 6450M's 4 GB frame buffer. The 5.32 TB/s bandwidth removes memory-bound bottlenecks in ways the 128.0 GB/s of the RX 6450M cannot approach. The 8192-bit bus width is the physical foundation of that bandwidth, and the HBM3 memory type operates at 1300 MHz with 5.2 Gbps effective data rate.

The Radeon RX 6450M wins on anything related to graphics output and driver support. It has display outputs, though they are portable device dependent, while the MI308X has no outputs at all. The RX 6450M supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4; the MI308X reports N/A for all three APIs. The RX 6450M also has 12 ray tracing cores, a feature absent from the MI308X's specification, and 32 ROPs that enable actual pixel rendering. The MI308X's 0 ROPs and 0 MPixel/s pixel rate confirm it is not intended for rasterized graphics.

The RX 6450M also wins on power efficiency and integration. At 50 W TDP, it consumes 700 W less than the MI308X's 750 W TDP. It requires no suggested PSU rating, while the MI308X calls for a 1150 W suggested PSU. The RX 6450M uses the PCIe 4.0 x4 interface, while the MI308X uses PCIe 5.0 x16. The RX 6450M is an IGP, meaning it can be integrated into a portable device, whereas the MI308X is an OAM module designed for server trays.

FAQ

Q: Which GPU has higher FP32 compute performance?

A: The AMD Instinct MI308X delivers 81.72 TFLOPS of FP32, while the AMD Radeon RX 6450M delivers 3.779 TFLOPS. The MI308X is approximately 21.6 times higher.

Q: How much memory does each GPU have?

A: The Instinct MI308X has 192 GB of HBM3 memory on an 8192-bit bus with 5.32 TB/s bandwidth. The Radeon RX 6450M has 4 GB of GDDR6 memory on a 64-bit bus with 128.0 GB/s bandwidth.

Q: Does either GPU support ray tracing?

A: The Radeon RX 6450M includes 12 ray tracing cores. The Instinct MI308X lists no ray tracing core count in its specification.

Q: Which GPU supports DirectX and Vulkan?

A: The Radeon RX 6450M supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The Instinct MI308X lists N/A for DirectX, OpenGL, and Vulkan.

Q: What is the power consumption difference?

A: The Instinct MI308X has a TDP of 750 W and a suggested PSU of 1150 W. The Radeon RX 6450M has a TDP of 50 W and no suggested PSU listed.

Q: What process nodes do the two GPUs use?

A: The Instinct MI308X uses TSMC's 5 nm process, while the Radeon RX 6450M uses TSMC's 6 nm process. The MI308X has 153,000 million transistors on a 1017 mm² die; the RX 6450M has 5,400 million transistors on a 107 mm² die.

Architecture Differences

The Instinct MI308X is built on the CDNA 3.0 architecture with the Aqua Vanjaram chip, part of the Instinct (MIx) generation. The Radeon RX 6450M uses the RDNA 2.0 architecture with the Navi 24 chip, part of the Radeon RX 6000 series in the Navi Mobile (RX 6000M) generation. The two architectures serve fundamentally different purposes: CDNA is compute-optimized for accelerators, while RDNA is graphics-optimized for rendering.

The process technology differs by one node generation. The MI308X uses TSMC's 5 nm process, while the RX 6450M uses TSMC's 6 nm process. The transistor counts reflect the scale difference: 153,000 million on the MI308X versus 5,400 million on the RX 6450M. Die size follows suit at 1017 mm² for the MI308X and 107 mm² for the RX 6450M. Transistor density is 150.4M per mm² for the MI308X and 50.5M per mm² for the RX 6450M, meaning the MI308X packs nearly three times more transistors per square millimeter.

Compute resources differ sharply. The MI308X has 19,456 shading units and 1,216 TMUs, but 0 ROPs. The RX 6450M has 768 shading units, 48 TMUs, and 32 ROPs. The MI308X has no ray tracing cores listed; the RX 6450M has 12. Neither part lists tensor cores.

Memory architecture is radically different. The MI308X uses HBM3 with 192 GB capacity, an 8192-bit bus, and 5.32 TB/s bandwidth, running at 1300 MHz with 5.2 Gbps effective. The RX 6450M uses GDDR6 with 4 GB capacity, a 64-bit bus, and 128.0 GB/s bandwidth, running at 2000 MHz with 16 Gbps effective. The MI308X's bus width is 128 times wider.

Clock speeds favor the smaller chip. The MI308X has a base clock of 1000 MHz and a boost clock of 2100 MHz. The RX 6450M has a base clock of 2000 MHz, a game clock of 2220 MHz, and a boost clock of 2460 MHz. The RX 6450M's higher clocks partially compensate for its smaller core count, but the MI308X's massive shading unit count still yields far higher aggregate throughput.

Form factor and interface also diverge. The MI308X is an OAM Module with a PCIe 5.0 x16 interface and no display outputs. The RX 6450M is an IGP with a PCIe 4.0 x4 interface and display outputs that are portable device dependent. The MI308X has no power connectors and a 750 W TDP with a suggested PSU of 1150 W. The RX 6450M also has no power connectors, a 50 W TDP, and no suggested PSU.

Release timing is close. The MI308X was released on December 5, 2023, while the RX 6450M was released on January 3, 2023. The MI308X's predecessor is Radeon Instinct, and the RX 6450M's predecessor is Polaris Mobile. The RX 6450M is marked as active in production; the MI308X has no production status listed. Neither part has a successor listed.

The MI308X reports a pixel rate of 0 MPixel/s and a texture rate of 2,553.6 GTexel/s. The RX 6450M reports a pixel rate of 78.72 GPixel/s and a texture rate of 118.1 GTexel/s. The absence of ROPs on the MI308X means it cannot perform final pixel output, reinforcing its role as a pure compute accelerator. The RX 6450M's 32 ROPs and full graphics API support make it a functional rendering solution for mobile devices.