AMD Instinct MI325X vs NVIDIA L20 Comparison

Head-to-Head Benchmarks

The recorded data contains no direct head-to-head benchmark results between the AMD Instinct MI325X and the NVIDIA L20. The MI325X has no entries in the benchmark database, with an average benchmark score of zero and a percentile ranking of 50 among all GPUs. The L20, by contrast, has two recorded benchmark scores: 274,276 in Geekbench OpenCL and 228,018 in Geekbench Vulkan, producing an average benchmark score of 251,147 and a percentile ranking of 99.

Because the MI325X lacks benchmark data, the comparison must rely on the L20's nearest rivals to contextualize its performance. The L20 sits 11.6% ahead of the NVIDIA PG506-232, which scores 225,124, and 14.2% ahead of the AMD Radeon PRO W7900D, which scores 219,827. In the opposite direction, the L20 trails the NVIDIA L40 by 11.6%, as that card scores 284,111, and falls 12.6% behind the NVIDIA RTX 6000 Ada Generation, which scores 287,237.

These deltas place the L20 in a mid-to-upper tier among server accelerators. The 14.2% margin over the W7900D and the 11.6% margin over the PG506-232 show clear wins against those specific competitors. The deficits against the L40 and RTX 6000 Ada are modest in percentage terms, indicating that the L20 operates within a narrow performance band around those higher-end parts rather than being decisively outclassed.

The absence of MI325X benchmarks means no direct win-loss tally can be computed. The database records zero wins for each product in head-to-head testing. This gap in measurements leaves the performance relationship between these two accelerators undefined by direct evidence. What the data does show is that the L20 has a substantial, verified performance footprint, while the MI325X has none recorded, which limits any quantitative comparison to architectural and specification analysis.

Architecture Differences

The two accelerators diverge fundamentally at the architecture level. The MI325X uses AMD's CDNA 3.0 architecture built on the Aqua Vanjaram chip, while the L20 uses NVIDIA's Ada Lovelace architecture built on the AD102 chip. Both are fabricated on TSMC's 5 nm process, but the transistor counts differ enormously. The MI325X packs 153,000 million transistors on a 1017 mm² die, yielding a transistor density of 150.4 million transistors per square millimeter. The L20 contains 76,300 million transistors on a 609 mm² die, with a density of 125.3 million per square millimeter. The MI325X die is 408 mm² larger and carries more than double the transistor count.

Memory architecture represents the starkest divide. The MI325X uses HBM3e memory with 256 GB capacity, an 8192-bit bus, and 6.14 TB/s of bandwidth. The L20 uses GDDR6 memory with 48 GB capacity, a 384-bit bus, and 864.0 GB/s of bandwidth. That is a 5.33x capacity advantage and a 7.1x bandwidth advantage for the MI325X. The memory clock figures reflect this: the MI325X memory runs at 1500 MHz with 6 Gbps effective data rate, while the L20 memory runs at 2250 MHz with 18 Gbps effective. The L20's higher memory clock per pin is irrelevant to overall throughput given the vastly narrower bus.

Compute resources also differ sharply. The MI325X has 19,456 shading units, 1,216 texture mapping units, and zero ROPs, which explains its 0 MPixel/s pixel rate. The L20 has 11,776 shading units, 368 TMUs, and 128 ROPs, producing a 322.6 GPixel/s pixel rate and a 927.4 GTexel/s texture rate. The MI325X texture rate is 2,553.6 GTexel/s, about 2.75x the L20's. The MI325X has no recorded RT cores or tensor cores, while the L20 has 92 RT cores and 368 tensor cores.

Floating-point throughput shows the MI325X's compute advantage. The MI325X delivers 81.72 TFLOPS for both FP32 and FP16, with a 1:1 ratio. The L20 delivers 59.35 TFLOPS for both FP32 and FP16, also 1:1. The MI325X leads by 37.7% in each precision. The L20's clock speeds are higher on paper: 1440 MHz base and 2520 MHz boost versus the MI325X's 1000 MHz base and 2100 MHz boost, but the MI325X's wider execution resources overcome that frequency deficit.

Feature support differs completely. The MI325X has no display outputs, no DirectX support, no OpenGL support, and no Vulkan support. The L20 has 4x DisplayPort 1.4a outputs, DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The MI325X is a pure compute accelerator with no graphics pipeline, while the L20 retains full graphics capability.

FAQ

Q: Which accelerator has more memory bandwidth?

A: The MI325X has 6.14 TB/s of bandwidth from its HBM3e memory on an 8192-bit bus. The L20 has 864.0 GB/s from GDDR6 memory on a 384-bit bus. The MI325X provides approximately 7.1 times the bandwidth.

Q: What is the power consumption difference?

A: The MI325X has a TDP of 1000 W and requires a 1400 W suggested power supply. The L20 has a TDP of 275 W and a 600 W suggested power supply. The L20 consumes 725 W less under its rated TDP.

Q: Does the MI325X support graphics APIs?

A: No. The MI325X has no display outputs and lists DirectX, OpenGL, and Vulkan support as N/A. The L20 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, and provides 4x DisplayPort 1.4a outputs.

Q: How does the L20 compare to its nearest rivals?

A: The L20 scores 11.6% higher than the NVIDIA PG506-232 and 14.2% higher than the AMD Radeon PRO W7900D. It scores 11.6% lower than the NVIDIA L40 and 12.6% lower than the NVIDIA RTX 6000 Ada Generation.

Q: What is the transistor density of each chip?

A: The MI325X has 153,000 million transistors on a 1017 mm² die, giving 150.4 million transistors per square millimeter. The L20 has 76,300 million transistors on a 609 mm² die, giving 125.3 million per square millimeter.

Q: Which accelerator has a higher FP32 throughput?

A: The MI325X delivers 81.72 TFLOPS in FP32, while the L20 delivers 59.35 TFLOPS. The MI325X leads by approximately 37.7% in this metric.

Specification Differences

The two accelerators differ across nearly every recorded specification. The MI325X uses the Aqua Vanjaram chip with CDNA 3.0 architecture, while the L20 uses the AD102 chip with Ada Lovelace architecture. The MI325X has 153,000 million transistors versus 76,300 million for the L20. Die size is 1017 mm² versus 609 mm². Transistor density is 150.4M per mm² versus 125.3M per mm².

Base clocks differ: 1000 MHz for the MI325X versus 1440 MHz for the L20. Boost clocks differ: 2100 MHz versus 2520 MHz. Memory clocks differ: 1500 MHz with 6 Gbps effective for the MI325X versus 2250 MHz with 18 Gbps effective for the L20. Memory capacity is 256 GB versus 48 GB. Memory type is HBM3e versus GDDR6. Bus width is 8192 bit versus 384 bit. Bandwidth is 6.14 TB/s versus 864.0 GB/s.

Shading units number 19,456 versus 11,776. TMUs number 1,216 versus 368. ROPs are 0 versus 128. The L20 has 92 RT cores and 368 tensor cores, while the MI325X has none recorded. Pixel rate is 0 MPixel/s versus 322.6 GPixel/s. Texture rate is 2,553.6 GTexel/s versus 927.4 GTexel/s. FP32 is 81.72 TFLOPS versus 59.35 TFLOPS. FP16 is likewise 81.72 TFLOPS versus 59.35 TFLOPS.

TDP is 1000 W versus 275 W. Slot width is OAM Module versus Dual-slot. Power connectors are None versus 1x 16-pin. Suggested PSU is 1400 W versus 600 W. Bus interface is PCIe 5.0 x16 versus PCIe 4.0 x16. Display outputs are No outputs versus 4x DisplayPort 1.4a. DirectX support is N/A versus 12 Ultimate (12_2). OpenGL is N/A versus 4.6. Vulkan is N/A versus 1.4. The L20 has dimensions of 267 mm length and 111 mm height, while the MI325X has no recorded dimensions. Release dates differ: 2024-10-09 for the MI325X versus 2023-11-15 for the L20. Production status is unrecorded for the MI325X but Active for the L20. The MI325X predecessor is Radeon Instinct; the L20 predecessor is Server Ampere and successor is Server Hopper.

Where Each One Wins

The MI325X wins decisively in raw compute throughput. Its 81.72 TFLOPS FP32 output exceeds the L20's 59.35 TFLOPS by 37.7%, a substantial margin for dense compute workloads. Texture rate favors the MI325X at 2,553.6 GTexel/s versus 927.4 GTexel/s, more than 2.75 times the L20's rate. Memory capacity and bandwidth are overwhelming advantages for the MI325X: 256 GB versus 48 GB capacity, and 6.14 TB/s versus 864.0 GB/s bandwidth. For workloads that scale with memory size or bandwidth, such as large model inference or training, the MI325X holds a categorical edge. Its PCIe 5.0 x16 interface also doubles the bus generation of the L20's PCIe 4.0 x16.

The L20 wins in every graphics-oriented metric. It has 128 ROPs producing a 322.6 GPixel/s pixel rate, while the MI325X has zero ROPs and zero pixel throughput. The L20 includes 92 RT cores and 368 tensor cores, neither of which the MI325X records. It supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, and provides four DisplayPort 1.4a outputs, making it usable for visualization, rendering, or any task requiring a display connection. The MI325X cannot output video at all.

Power efficiency favors the L20. At 275 W TDP versus 1000 W, the L20 draws 725 W less. The L20's suggested PSU is 600 W compared to 1400 W for the MI325X. For FP32 per watt, the L20 delivers 59.35 TFLOPS divided by 275 W, approximately 0.216 TFLOPS per watt, while the MI325X delivers 81.72 TFLOPS divided by 1000 W, approximately 0.0817 TFLOPS per watt. The L20 is roughly 2.64 times more power-efficient in raw FP32 throughput per watt. The L20 also has a dual-slot form factor versus the OAM Module form factor of the MI325X, and it has a recorded active production status while the MI325X does not.

The L20's benchmark percentile of 99 versus the MI325X's 50 reflects verified performance presence. The L20 has measurable scores in Geekbench OpenCL and Vulkan, while the MI325X has no benchmark entries. The L20's nearest rival comparisons show it outperforming the PG506-232 by 11.6% and the W7900D by 14.2%, placing it in a competitive position among tested accelerators.

The Verdict

The data points to two distinct products serving different roles. The AMD Instinct MI325X is a high-capacity compute accelerator with massive memory, wide bandwidth, and high FP32 throughput, but it lacks graphics capabilities, display outputs, and any benchmark results. The NVIDIA L20 is a verified, power-efficient server accelerator with graphics support, ray tracing cores, tensor cores, and a strong benchmark record at the 99th percentile.

For workloads that require maximum memory capacity and bandwidth, such as holding very large models or datasets in memory, the MI325X is the clear choice based on its 256 GB HBM3e configuration and 6.14 TB/s bandwidth. Its 81.72 TFLOPS FP32 output also exceeds the L20 by a solid margin. The absence of benchmark data for the MI325X means its real-world performance cannot be confirmed, but the specification sheet indicates superior raw compute and memory resources.

For workloads that need graphics output, ray tracing, or tensor core acceleration, the L20 is the only option between the two. It provides display outputs, API support, and a full graphics pipeline. Its power draw of 275 W is dramatically lower than the MI325X's 1000 W, and its benchmark scores place it above the PG506-232 and W7900D while trailing the L40 and RTX 6000 Ada by modest margins. The L20 also uses a standard dual-slot form factor with a 16-pin power connector, making it more adaptable to conventional server configurations than the OAM Module format of the MI325X.

The FP32 per watt calculation favors the L20 by approximately 2.64 times. The L20's 99th percentile ranking indicates strong measured performance among all GPUs, while the MI325X's 50th percentile is a placeholder given zero benchmark entries. The release dates show the MI325X launched in October 2024, nearly a year after the L20 in November 2023, with the L20 still in active production.

The choice depends entirely on the workload's nature. The MI325X targets compute-first, memory-bound scenarios with no graphics requirements. The L20 targets a broader set of tasks including graphics, ray tracing, and compute, with verified performance and far lower power consumption. The database contains no head-to-head test results, so the final judgment rests on the recorded specifications and the L20's benchmark profile.