AMD Instinct MI308X vs NVIDIA RTX 4500 Ada Generation Comparison

The Verdict

The AMD Instinct MI308X and NVIDIA RTX 4500 Ada Generation target entirely different segments, and the data confirms they are not direct competitors. The MI308X is a compute-oriented accelerator with a 50th percentile ranking across all GPUs, while the RTX 4500 Ada Generation sits at the 97th percentile with recorded benchmark scores. The RTX 4500 Ada Generation is the clear choice for any workload that relies on standard graphics APIs, as it supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, whereas the MI308X reports no API support at all.

The MI308X, despite its lower percentile ranking, offers vastly larger memory capacity and bandwidth, making it suitable for data-center scale compute tasks that exceed the RTX 4500's 24 GB frame buffer. The RTX 4500 Ada Generation is the only one of the two with any recorded benchmark data, scoring 160,786 in Geekbench OpenCL and 171,401 in Geekbench Vulkan, giving it an average benchmark score of 166,094. For users who need a working graphics card with display outputs, the RTX 4500 is the only viable option, as the MI308X has no display outputs whatsoever.

Architecture Differences

The two accelerators are built on different architectural foundations. The AMD Instinct MI308X uses the CDNA 3.0 architecture with the Aqua Vanjaram chip, fabricated on a 5 nm process at TSMC. The NVIDIA RTX 4500 Ada Generation uses the Ada Lovelace architecture with the AD103 chip, also fabricated on a 5 nm process at TSMC. Both share the same process node and foundry, but the similarities end there.

The MI308X packs 153,000 million transistors on a 1017 mm² die, resulting in a transistor density of 150.4 million per square millimeter. The RTX 4500 Ada Generation contains 45,900 million transistors on a 379 mm² die, for a density of 121.1 million per square millimeter. The MI308X is a much larger and more complex chip, with over three times the transistor count and nearly three times the die area.

The feature sets diverge sharply. The MI308X has no RT cores, no tensor cores, and reports zero ROPs. It also has no DirectX, OpenGL, or Vulkan support, and no display outputs. The RTX 4500 Ada Generation includes 60 RT cores and 240 tensor cores, along with 80 ROPs, and supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4. It also provides four DisplayPort 1.4a outputs for direct display connectivity.

Head-to-Head Benchmarks

The recorded data shows only one side with benchmark results. The NVIDIA RTX 4500 Ada Generation has two Geekbench scores: 160,786 in OpenCL and 171,401 in Vulkan. Its average benchmark score is 166,094. The AMD Instinct MI308X has no benchmark entries in the database, so no direct comparison of measured performance is possible from the recorded data.

The RTX 4500 Ada Generation's nearest rivals provide context for its performance level. The NVIDIA RTX A5500 scores 165,217, which is 0.5% below the RTX 4500. The AMD Radeon PRO W7800 scores 164,894, 0.7% lower. The AMD Radeon Pro W6900X scores 168,574, which is 1.5% higher than the RTX 4500. The NVIDIA A100 PCIe 40 GB scores 162,504, 2.2% lower. These deltas place the RTX 4500 in a tightly contested group, with the closest rival being the RTX A5500 at just 0.5% behind.

The MI308X has no nearest rivals listed and no benchmark scores, so its competitive positioning cannot be quantified from the database. The percentile data indicates it ranks at the 50th percentile across all GPUs, while the RTX 4500 ranks at the 97th percentile, a substantial gap in overall standing.

Specification Differences

The two accelerators differ across nearly every specification category. The MI308X has 19,456 shading units, 1,216 TMUs, and 0 ROPs. The RTX 4500 Ada Generation has 7,680 shading units, 240 TMUs, and 80 ROPs. The MI308X has more than double the shading units and five times the TMUs, but no ROPs at all.

Memory configurations are dramatically different. The MI308X uses 192 GB of HBM3 on an 8192-bit bus, delivering 5.32 TB/s of bandwidth. The RTX 4500 uses 24 GB of GDDR6 on a 192-bit bus, providing 432.0 GB/s. The MI308X offers eight times the capacity and over twelve times the bandwidth.

Clock speeds also differ. The MI308X has a base clock of 1000 MHz and a boost clock of 2100 MHz, with memory clocked at 1300 MHz (5.2 Gbps effective). The RTX 4500 runs at a base of 2070 MHz and a boost of 2580 MHz, with memory at 2250 MHz (18 Gbps effective). The RTX 4500 has significantly higher clock speeds, but the MI308X compensates with its massive memory bus.

Compute rates show the MI308X's advantage. The MI308X delivers 81.72 TFLOPS in both FP32 and FP16 (1:1). The RTX 4500 delivers 39.63 TFLOPS in both FP32 and FP16 (1:1). The MI308X is roughly twice as fast in raw floating-point throughput. Texture rate follows a similar pattern: 2,553.6 GTexel/s for the MI308X versus 619.2 GTexel/s for the RTX 4500. Pixel rate, however, is 0 MPixel/s for the MI308X and 206.4 GPixel/s for the RTX 4500.

Power requirements are vastly different. The MI308X has a TDP of 750 W and a suggested PSU of 1150 W. The RTX 4500 has a TDP of 210 W and a suggested PSU of 550 W. The MI308X uses an OAM module slot width with no power connectors, while the RTX 4500 is a dual-slot card also with no power connectors listed.

The bus interfaces differ: the MI308X uses PCIe 5.0 x16, while the RTX 4500 uses PCIe 4.0 x16. Physical dimensions are only listed for the RTX 4500: 245 mm length (9.6 inches) and 112 mm height (4.4 inches). The MI308X has no dimensions recorded.

Release dates are also distinct. The MI308X was released on December 5, 2023, while the RTX 4500 Ada Generation was released earlier on August 8, 2023. The RTX 4500's predecessor is Workstation Ampere, and its successor is Blackwell PRO W. The MI308X's predecessor is Radeon Instinct, with no successor listed.

FAQ

Q: Which GPU has higher raw floating-point performance?

A: The AMD Instinct MI308X delivers 81.72 TFLOPS in both FP32 and FP16, which is more than double the RTX 4500 Ada Generation's 39.63 TFLOPS in both formats.

Q: Does the AMD Instinct MI308X support any graphics APIs?

A: No. The database records DirectX, OpenGL, and Vulkan as N/A for the MI308X, and it has no display outputs. The RTX 4500 Ada Generation supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4.

Q: How much memory does each card have and what is the bandwidth?

A: The MI308X has 192 GB of HBM3 on an 8192-bit bus with 5.32 TB/s bandwidth. The RTX 4500 Ada Generation has 24 GB of GDDR6 on a 192-bit bus with 432.0 GB/s bandwidth.

Q: Which card has a higher percentile ranking among all GPUs?

A: The RTX 4500 Ada Generation ranks at the 97th percentile, while the AMD Instinct MI308X ranks at the 50th percentile.

Q: What are the power consumption requirements for each card?

A: The MI308X has a TDP of 750 W and a suggested PSU of 1150 W. The RTX 4500 Ada Generation has a TDP of 210 W and a suggested PSU of 550 W.

Q: Does the RTX 4500 Ada Generation have any recorded benchmark scores?

A: Yes. It scores 160,786 in Geekbench OpenCL and 171,401 in Geekbench Vulkan, with an average of 166,094. The MI308X has no recorded benchmark scores in the database.

Where Each One Wins

The AMD Instinct MI308X wins in compute density and memory capacity. Its 192 GB of HBM3 with 5.32 TB/s bandwidth dwarfs the RTX 4500's 24 GB and 432.0 GB/s. For workloads that require holding very large datasets in memory, such as high-performance computing or large-scale model training, the MI308X's memory subsystem is in a different class. Its 81.72 TFLOPS FP32 and FP16 performance is also roughly double the RTX 4500's 39.63 TFLOPS, giving it a clear advantage in raw compute throughput. The MI308X also has more shading units (19,456 versus 7,680), more TMUs (1,216 versus 240), and a faster texture rate (2,553.6 GTexel/s versus 619.2 GTexel/s).

The NVIDIA RTX 4500 Ada Generation wins in every area related to graphics and integration. It has 60 RT cores and 240 tensor cores, which the MI308X lacks entirely. It provides 80 ROPs with a pixel rate of 206.4 GPixel/s, while the MI308X has 0 ROPs and 0 MPixel/s. The RTX 4500 supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, making it usable for rendering and graphics workloads, while the MI308X has no API support. It also has four DisplayPort 1.4a outputs, whereas the MI308X has none.

The RTX 4500 wins on efficiency and physical footprint. Its 210 W TDP is less than a third of the MI308X's 750 W, and its suggested PSU of 550 W is less than half of the MI308X's 1150 W. The RTX 4500 is a dual-slot card with a 245 mm length, while the MI308X is an OAM module. The RTX 4500 also uses PCIe 4.0 x16, which is more common in existing systems, while the MI308X requires PCIe 5.0 x16.

The recorded benchmark data favors the RTX 4500, which has an average score of 166,094 and a 97th percentile ranking. Its nearest rival, the NVIDIA RTX A5500, is only 0.5% behind, while the AMD Radeon Pro W6900X is 1.5% ahead. The MI308X has no benchmark scores and sits at the 50th percentile, so the database does not support any performance comparison between the two based on measured results.

In summary, the MI308X is built for memory-bound and compute-heavy workloads where graphics output is irrelevant, while the RTX 4500 Ada Generation is a complete workstation solution with rendering, ray tracing, and display capabilities at a fraction of the power draw. The choice depends entirely on whether the workload requires graphics functionality or pure compute and memory scale.