AMD Instinct MI300X vs AMD Instinct MI325X Comparison

Head-to-Head Benchmarks

The recorded data for these two accelerators is limited to a single Geekbench OpenCL result for the MI300X, while the MI325X has no benchmark entries in the database at this time. The MI300X scores 317,994 points, which places it at the 100th percentile against all GPUs in the database. This means the MI300X outperforms every other recorded GPU in this specific test. For context, the nearest rivals to the MI300X include the NVIDIA B200 with an average score of 345,482 (8% higher), the NVIDIA H200 NVL with 334,891 (5% higher), the NVIDIA L40S with 295,763 (7.5% lower), and the NVIDIA RTX 6000 Ada Generation with 287,237 (10.7% lower). The MI300X sits between the H200 NVL and the L40S in raw OpenCL performance, trailing the top NVIDIA accelerators but clearly ahead of the workstation-class options.

The MI325X has no recorded benchmark scores, so direct head-to-head comparison of measured performance is impossible from the database. The average benchmark score for the MI325X is listed as zero, and its percentile against all GPUs is 50, which reflects the absence of data rather than actual performance. The MI300X, by contrast, has a solid measured result. Without a benchmark entry for the MI325X, the database cannot confirm whether the newer accelerator is faster in OpenCL, and no wins are recorded for either product in the head-to-head data.

The specifications suggest why the MI325X might differ in performance, but the benchmark data does not verify it. Both cards use the same chip, the same architecture, and the same core configuration, so the compute throughput figures are identical on paper. The MI325X raises memory clock speed from 1300 MHz to 1500 MHz, which increases effective memory data rate from 5.2 Gbps to 6 Gbps. It also expands memory capacity from 192 GB to 256 GB and switches from HBM3 to HBM3e. Memory bandwidth climbs from 5.32 TB/s to 6.14 TB/s, a meaningful increase of over 15%. These changes could translate into higher real-world scores in memory-bound workloads, but no measurement exists in the database to confirm it.

The MI300X has a clear advantage in the database: it has a measured score, and the MI325X does not. For anyone relying on recorded data, the MI300X is the only one of the two with verified performance. The MI325X remains an unmeasured entry, so any claims about its speed relative to the MI300X would have to come from external testing, not from this database.

The Verdict

The data indicates that the MI300X is the only one of these two accelerators with a benchmark result. Its Geekbench OpenCL score of 317,994 places it at the 100th percentile among all GPUs in the database, and it outperforms the NVIDIA L40S by 7.5% and the RTX 6000 Ada Generation by 10.7%. The MI325X has no recorded score, so the database cannot verify its performance in any test. The verdict from the recorded data is straightforward: the MI300X is the proven performer, while the MI325X is an unverified entry with no measured results.

That said, the specification differences provide a hint of what the MI325X could deliver if benchmarked. It offers 256 GB of HBM3e memory versus 192 GB of HBM3 on the MI300X, and its memory bandwidth is 6.14 TB/s versus 5.32 TB/s. These are substantial increases in memory capacity and throughput, and they come at the cost of higher power draw: the MI325X is rated at 1000 W versus 750 W for the MI300X, with a suggested PSU of 1400 W versus 1150 W. The MI325X also runs its memory at a higher clock speed, 1500 MHz versus 1300 MHz.

Who should pick which, strictly from the data? Anyone who needs verified performance should pick the MI300X, because it has a measured score and the MI325X does not. Anyone who needs more memory capacity or higher memory bandwidth should consider the MI325X, since those are the only areas where the database shows a clear difference. Compute performance is identical on paper: both have 19,456 shading units, 1,216 TMUs, 81.72 TFLOPS FP32, and 81.72 TFLOPS FP16. The MI325X is the newer release, dated October 2024 versus December 2023, but that alone does not make it faster in any recorded test.

FAQ

Q: Which GPU has a higher Geekbench OpenCL score in the database?

A: The AMD Instinct MI300X has a recorded Geekbench OpenCL score of 317,994. The AMD Instinct MI325X has no benchmark entries in the database, so its score is not recorded.

Q: How does the MI300X compare to its nearest rivals in the database?

A: The MI300X scores 7.5% higher than the NVIDIA L40S and 10.7% higher than the NVIDIA RTX 6000 Ada Generation. It scores 5% lower than the NVIDIA H200 NVL and 8% lower than the NVIDIA B200.

Q: What is the memory capacity difference between the two accelerators?

A: The MI300X has 192 GB of HBM3 memory, while the MI325X has 256 GB of HBM3e memory. Both use an 8192-bit memory bus.

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

A: The MI300X has a memory bandwidth of 5.32 TB/s, while the MI325X has a memory bandwidth of 6.14 TB/s. The MI325X also runs its memory at 1500 MHz (6 Gbps effective) versus 1300 MHz (5.2 Gbps effective) on the MI300X.

Q: Do the two accelerators have the same compute specifications?

A: Yes. Both have 19,456 shading units, 1,216 TMUs, 81.72 TFLOPS FP32, and 81.72 TFLOPS FP16. Their base clock is 1000 MHz and their boost clock is 2100 MHz on both cards.

Q: What are the power requirements for each card?

A: The MI300X has a TDP of 750 W and a suggested PSU of 1150 W. The MI325X has a TDP of 1000 W and a suggested PSU of 1400 W.

Specification Differences

The two accelerators differ in several specification fields. The MI300X uses HBM3 memory with a capacity of 192 GB, while the MI325X uses HBM3e memory with a capacity of 256 GB. Memory clock speeds differ as well: the MI300X runs at 1300 MHz (5.2 Gbps effective), while the MI325X runs at 1500 MHz (6 Gbps effective). Memory bandwidth is 5.32 TB/s on the MI300X and 6.14 TB/s on the MI325X.

Power consumption is another clear difference. The MI300X has a TDP of 750 W and a suggested PSU of 1150 W. The MI325X has a TDP of 1000 W and a suggested PSU of 1400 W. Both are OAM modules with no power connectors and no display outputs.

Release dates differ as well. The MI300X was released on December 5, 2023, while the MI325X was released on October 9, 2024. Both have the same chip, the same architecture, the same process node, the same foundry, the same transistor count, the same die size, the same transistor density, the same shading units, the same TMUs, the same texture rate, the same FP32 and FP16 throughput, the same bus interface, and the same API support (all N/A). Both have no RT cores, no tensor cores, and no ROPs, with a pixel rate of 0 MPixel/s.

Architecture Differences

The architecture section shows more similarities than differences. Both cards use the Aqua Vanjaram chip built on CDNA 3.0 architecture, manufactured on a 5 nm process at TSMC. Both have 153,000 million transistors on a 1017 mm² die, giving a transistor density of 150.4M per mm². The memory subsystem is where the architecture diverges: the MI300X pairs the chip with HBM3, while the MI325X uses HBM3e. This is a memory technology change, not a core architecture change. The MI325X increases memory capacity by 64 GB, raises the memory clock by 200 MHz, and adds 0.82 TB/s of bandwidth. The compute architecture, including the 19,456 shading units and the 1:1 FP16 to FP32 ratio, is unchanged. The MI325X also carries the same boost clock of 2100 MHz, so the architecture does not appear to have been re-tuned for higher core clocks. The power envelope is larger on the MI325X, which may allow the memory subsystem to run at higher speeds without affecting the core clocks. The database shows no differences in cache, tensor cores, or ray tracing hardware, as those fields are either null or not listed for both products.

Where Each One Wins

The MI300X wins in the only measured category in the database. It has a Geekbench OpenCL score of 317,994, while the MI325X has no recorded benchmark. The MI300X also wins on power efficiency in a strict sense: it draws 750 W versus 1000 W, and it achieves its measured score at that lower power level. The MI325X, with no benchmark data, cannot claim any measured performance win. The MI300X also wins on verified availability in the database, with a release date of December 2023 and a full specification list backed by a benchmark result.

The MI325X wins on paper in the memory category. It has 256 GB of HBM3e versus 192 GB of HBM3, and its bandwidth of 6.14 TB/s exceeds the MI300X's 5.32 TB/s. For workloads that are limited by memory capacity or memory bandwidth, the MI325X appears better suited based on the specification data. It also has a higher memory clock, 1500 MHz versus 1300 MHz. The MI325X is the newer product, released in October 2024, which may indicate a longer support horizon, but the database does not include any performance data to confirm a practical advantage.

For compute-heavy tasks that are not memory-bound, the two cards are identical on paper. Both deliver 81.72 TFLOPS FP32 and 81.72 TFLOPS FP16, with the same shading unit count, the same TMU count, and the same texture rate. The MI300X is the clear pick for anyone who wants a measured result in the database. The MI325X is the pick for anyone who needs the larger memory pool and higher bandwidth, accepting that no benchmark data exists to verify its performance. The wins are split cleanly: measured performance goes to the MI300X, memory specifications go to the MI325X.