GPU Comparison

The NVIDIA L20 and AMD Radeon PRO W6800 represent two distinct philosophies in professional graphics, with the data showing a decisive performance gap that underscores their different target markets. The L20, built on the Ada Lovelace architecture, arrives nearly two and a half years after the W6800, and the benchmark results reflect that generational leap in raw compute and API efficiency.

Head-to-Head Benchmarks

The head-to-head results are unambiguous, with the NVIDIA L20 winning both available benchmarks by a massive margin. In Geekbench OpenCL, the L20 scores 274,276 against the W6800’s 121,808, yielding a delta of 125.2% in NVIDIA’s favor. This is not a marginal victory; it is a complete domination, with the L20 delivering more than double the compute throughput in this test.

The Vulkan results tell a similar story, though the gap narrows slightly. The L20 posts 228,018 versus the W6800’s 109,961, a 107.4% advantage. While still a decisive win, the smaller delta in Vulkan suggests that the AMD card’s RDNA 2.0 architecture handles the lower-level API relatively better than it does OpenCL, though it remains firmly in second place.

To contextualize these scores, the L20’s average benchmark score of 251,147 places it in the 99th percentile of all GPUs. Its nearest rival, the NVIDIA L40, scores 284,111, which is 11.6% higher, while the RTX 6000 Ada Generation sits at 287,237, 12.6% higher. This positions the L20 as a high-tier professional card, just below the absolute flagship Ada offerings. In contrast, the W6800’s average score of 135,396 lands in the 96th percentile, with its closest rivals, the NVIDIA A10M, RTX 4000 Ada Generation, and AMD Radeon Pro W6800X Duo, all within a 0.8% delta, indicating a tightly contested mid-range segment where the W6800 is competitive but not dominant.

The data implies that the L20 is not merely faster; it is in a different performance class entirely. The 125.2% OpenCL delta is almost the exact difference one would expect when comparing a 48 GB compute monster against a 32 GB workstation card, and the benchmark scores reinforce that the L20 is designed for heavy computational workloads where the W6800 would struggle to keep pace.

Architecture Differences

The architectural chasm between these two cards is stark and explains the benchmark disparity. The NVIDIA L20 uses the AD102 chip on a 5 nm TSMC process, packing 76,300 million transistors into a 609 mm² die, yielding a transistor density of 125.3 million per square millimeter. This is the Ada Lovelace architecture at its most refined, focusing on sheer compute density and efficiency.

The AMD Radeon PRO W6800, by contrast, relies on the Navi 21 chip fabricated on a 7 nm TSMC process. It contains 26,800 million transistors on a 520 mm² die, resulting in a density of just 51.5 million per square millimeter. This older RDNA 2.0 design is less dense and, as the benchmarks show, less efficient at raw compute tasks.

The compute resources diverge dramatically. The L20 boasts 11,776 shading units, 368 texture mapping units, 128 ROPs, 92 RT cores, and 368 tensor cores. The W6800 counters with 3,840 shading units, 240 TMUs, 96 ROPs, and 60 RT cores, but notably lacks tensor cores entirely. This absence is critical for AI and machine learning workloads, which rely heavily on tensor core acceleration, an area where the L20 has a fundamental architectural advantage that no driver optimization can overcome.

Memory subsystems also differ substantially. The L20 offers 48 GB of GDDR6 on a 384-bit bus, delivering 864.0 GB/s of bandwidth. The W6800 provides 32 GB of GDDR6 on a 256-bit bus, yielding 512.0 GB/s. The L20’s 68.75% bandwidth advantage directly supports its higher compute throughput, especially in memory-bound professional applications.

Clock speeds tell a nuanced story. The W6800 has a higher base clock at 1575 MHz versus the L20’s 1440 MHz, but the L20’s boost clock of 2520 MHz exceeds the W6800’s 2322 MHz. The L20 also runs its memory at 2250 MHz (18 Gbps effective) compared to the W6800’s 2000 MHz (16 Gbps effective). The L20’s FP32 performance of 59.35 TFLOPS dwarfs the W6800’s 17.83 TFLOPS, a 233% advantage, while its FP16 throughput is identical at 59.35 TFLOPS (1:1 ratio), whereas the W6800 achieves 35.67 TFLOPS only through a 2:1 shader ratio.

FAQ

Q: Which GPU has higher raw compute performance?

A: The NVIDIA L20 dominates with 59.35 TFLOPS of FP32 performance versus the AMD W6800’s 17.83 TFLOPS, a 233% advantage. The L20 also leads in pixel rate (322.6 GPixel/s vs 222.9 GPixel/s) and texture rate (927.4 GTexel/s vs 557.3 GTexel/s).

Q: How do their memory capacities affect real-world usage?

A: The L20 provides 48 GB of GDDR6 on a 384-bit bus with 864.0 GB/s bandwidth, while the W6800 offers 32 GB on a 256-bit bus at 512.0 GB/s. The L20’s 16 GB extra capacity and 68.75% higher bandwidth make it better suited for large datasets and high-resolution textures.

Q: Does the AMD card have any advantage in API support?

A: Both cards support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, so there is no difference in API compatibility. However, the L20 includes tensor cores for AI workloads, which the W6800 lacks entirely.

Q: What does the power draw difference imply?

A: The L20 is rated at 275 W TDP versus the W6800’s 250 W, a modest 25 W increase for the significantly faster card. Both require a 600 W power supply, but the L20 uses a single 16-pin connector while the W6800 uses a 6-pin and 8-pin combo.

Q: Is the W6800 still competitive in any benchmark?

A: The head-to-head data shows the W6800 wins zero benchmarks against the L20. Its closest rivals in the overall percentile rankings are within a 0.8% delta, but against the L20, it trails by over 100% in both OpenCL and Vulkan.

Q: Why does the L20 have a higher percentile ranking?

A: The L20 sits in the 99th percentile of all GPUs with an average score of 251,147, while the W6800 is in the 96th percentile with 135,396. The 85.5% gap in average scores explains the three-percentile difference.

The Verdict

The data is unambiguous: the NVIDIA L20 is the superior performer in every measured category. It wins both head-to-head benchmarks with deltas exceeding 107%, offers 50% more memory, delivers 233% more FP32 throughput, and includes tensor cores for AI acceleration. Its 99th percentile ranking places it among the elite GPUs, just 11.6% behind the L40 and 12.6% behind the RTX 6000 Ada Generation.

The AMD Radeon PRO W6800, while a competent workstation card in the 96th percentile, is clearly outclassed. Its closest rivals, the NVIDIA A10M and RTX 4000 Ada Generation, score within 0.1% of its average, indicating it competes in a mid-range tier where it performs admirably. However, against the L20, it has no competitive footing.

The production status reinforces this hierarchy. The L20 is listed as Active, while the W6800 is End-of-life, suggesting AMD has moved on from this design. The L20’s release in November 2023 versus the W6800’s June 2021 release means buyers choosing the L20 are investing in current technology, while the W6800 represents a prior generation. For any workload that demands maximum compute performance, the L20 is the clear choice based on the benchmark data.

Specification Differences

| Specification | NVIDIA L20 | AMD Radeon PRO W6800 |

|---|---|---|

| Architecture | Ada Lovelace | RDNA 2.0 |

| Process Node | 5 nm | 7 nm |

| Transistors | 76,300 million | 26,800 million |

| Die Size | 609 mm² | 520 mm² |

| Memory Size | 48 GB | 32 GB |

| Memory Bus Width | 384 bit | 256 bit |

| Memory Bandwidth | 864.0 GB/s | 512.0 GB/s |

| Base Clock | 1440 MHz | 1575 MHz |

| Boost Clock | 2520 MHz | 2322 MHz |

| Shading Units | 11,776 | 3,840 |

| TMUs | 368 | 240 |

| ROPs | 128 | 96 |

| RT Cores | 92 | 60 |

| Tensor Cores | 368 | None |

| FP32 Performance | 59.35 TFLOPS | 17.83 TFLOPS |

| FP16 Performance | 59.35 TFLOPS (1:1) | 35.67 TFLOPS (2:1) |

| TDP | 275 W | 250 W |

| Power Connectors | 1x 16-pin | 1x 6-pin + 1x 8-pin |

| Display Outputs | 4x DisplayPort 1.4a | 6x mini-DisplayPort 1.4a |

| Dimensions (H) | 111 mm | 120 mm |

| Dimensions (W) | Not specified | 50 mm |

| Production Status | Active | End-of-life |

| Release Date | 2023-11-15 | 2021-06-07 |

| Transistor Density | 125.3M / mm² | 51.5M / mm² |

Where Each One Wins

The NVIDIA L20 wins in every scenario where raw compute is the primary requirement. Its 59.35 TFLOPS FP32 performance, 864.0 GB/s memory bandwidth, and 48 GB capacity make it ideal for large-scale scientific computing, complex 3D rendering, and AI inference tasks that benefit from its 368 tensor cores. The 125.2% OpenCL advantage and 107.4% Vulkan advantage mean that any application leveraging these APIs will see dramatic performance improvements on the L20.

The AMD Radeon PRO W6800, despite losing all benchmarks to the L20, still has a defined use case. Its lower 250 W TDP and dual-slot design (same as the L20) make it suitable for multi-GPU configurations where power density is a concern. The 6x mini-DisplayPort 1.4a outputs versus the L20’s 4x DisplayPort 1.4a could be advantageous for multi-display setups that do not require maximum compute. Its 32 GB memory remains sufficient for many professional visualization tasks, and its 96th percentile ranking shows it is not a weak card, it simply faces a superior opponent.

The production status is the final differentiator. The L20’s Active status ensures ongoing availability and support, while the W6800’s End-of-life designation suggests buyers should look to newer options. The W6800’s only practical wins are in power efficiency per teraflop (250 W for 17.83 TFLOPS versus 275 W for 59.35 TFLOPS) and physical width, but these are minor considerations when the performance gap is as vast as the data shows. For any buyer prioritizing compute performance, the L20 is the only rational choice.