NVIDIA L4 vs NVIDIA Rubin GPU Comparison

Where Each One Wins

The recorded data paints a clear picture of two devices built for entirely different segments of the server market. The NVIDIA L4 is a low-power, single-slot accelerator with active benchmark scores, while the NVIDIA Rubin GPU has no recorded benchmark scores in the database. This absence of data is itself informative: the Rubin GPU is positioned as a next-generation compute platform, not a legacy graphics workload device.

For the L4, the wins are measurable. It posts a Geekbench OpenCL score of 140,838 and a Geekbench Vulkan score of 121,306. Its average benchmark score across recorded tests is 131,072, placing it in the 95th percentile of all GPUs tracked. That percentile ranking indicates the L4 sits comfortably ahead of the vast majority of graphics hardware in the database, despite its modest power envelope.

The Rubin GPU, by contrast, has an average benchmark score of 0, sits in the 50th percentile, and has no nearest rivals listed. Its benchmark array is empty. The data shows zero recorded wins in head-to-head tests for either device, which reflects the fact that no direct comparative benchmarks exist between these two products. The Rubin GPU's wins, if any, cannot be quantified from the database because no tests have been run or recorded.

The functional split is therefore straightforward. The L4 wins in any scenario requiring immediate, verified compute results with a standard software stack. The Rubin GPU wins in raw hardware capability, but only on paper, not in measured performance. Users needing a working accelerator today would choose the L4 based on its demonstrated scores. Users planning a future deployment with the Rubin GPU's massive resources would be betting on hardware specifications rather than recorded results.

Architecture Differences

The architectural gap between these two is generational and physical. The L4 uses the AD104 chip on the Ada Lovelace architecture, fabricated on a 5 nm process at TSMC. The Rubin GPU uses the GR100 chip on the Rubin architecture, fabricated on a 3 nm process, also at TSMC. This process shrink is significant: the L4 packs 35,800 million transistors into a 294 mm² die, while the Rubin GPU holds 336,000 million transistors on a 1456 mm² die. Transistor density rises from 121.8 million per square millimeter on the L4 to 230.8 million per square millimeter on the Rubin GPU.

The L4 belongs to the Server Ada generation (Lxx), while the Rubin GPU belongs to the Server Rubin generation (Rxx). Their predecessors and successors also differ. The L4 follows Server Ampere and leads to Server Hopper. The Rubin GPU follows Server Blackwell and has no recorded successor.

Clock behavior diverges substantially. The L4 has a base clock of 795 MHz and a boost clock of 2040 MHz. The Rubin GPU runs a lower base clock of 700 MHz but boosts higher to 2267 MHz. Memory clocks tell a different story: the L4 uses a 1563 MHz memory clock with 12.5 Gbps effective data rate, while the Rubin GPU runs 2695 MHz with 10.8 Gbps effective. The higher physical clock on the Rubin GPU does not translate to a higher effective rate because of the different memory types.

Shading resources are dramatically different. The L4 has 7,424 shading units, 240 texture mapping units, and 80 raster operations units. The Rubin GPU has 28,720 shading units, 896 texture mapping units, and only 24 raster operations units. The Rubin GPU's raster operations count being lower than the L4's suggests it is not designed for traditional pixel-pushing workloads. The L4 carries 60 ray tracing cores and 240 tensor cores; the Rubin GPU has no recorded ray tracing core count but does list 896 tensor cores.

The L4 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The Rubin GPU lists N/A for all three APIs, which the database records as unavailable. This is a fundamental divergence: one device is a graphics-capable accelerator, the other is a compute-focused module with no consumer graphics API support.

Head-to-Head Benchmarks

The head-to-head benchmark array in the database is empty. There are no recorded tests where both the L4 and the Rubin GPU ran the same workload. This means the direct comparison must be built from the L4's individual scores and the Rubin GPU's absence of scores.

The L4's Geekbench OpenCL result of 140,838 places it within a tight cluster of rival accelerators. Its nearest rival, the NVIDIA GeForce RTX 3090 Ti, averages 131,938, which puts the L4 at 0.7% behind. The NVIDIA RTX 4000 Ada Generation averages 135,218, and the L4 trails by 3.1%. The NVIDIA A10M also averages 135,230, a 3.1% gap. The AMD Radeon PRO W6800 averages 135,396, again a 3.2% deficit. These deltas are small, indicating the L4 delivers performance on par with much larger, higher-power desktop and workstation cards.

For the Vulkan test, the L4 scores 121,306. This is lower than its OpenCL result, which is common for devices optimized for compute rather than graphics presentation. The Vulkan score still contributes to an average benchmark score of 131,072.

The Rubin GPU has no such numbers. Its average benchmark score is recorded as 0, and its percentile is 50, which is the median by definition when no tests exist. The database offers no evidence of how the Rubin GPU would perform in OpenCL or Vulkan. Any claim of superiority for the Rubin GPU must rest on its hardware specifications, not on measured outcomes.

The biggest win for the L4 is therefore the existence of verified performance data. The biggest win for the Rubin GPU is its raw hardware capacity, which the L4 cannot match. But without benchmark results, the Rubin GPU's advantage remains theoretical.

Specification Differences

The two devices differ in nearly every measurable specification. The L4 is built on a 5 nm process with 35,800 million transistors and a 294 mm² die. The Rubin GPU uses a 3 nm process with 336,000 million transistors and a 1456 mm² die. The L4's transistor density is 121.8 million per square millimeter; the Rubin GPU's is 230.8 million per square millimeter.

Base clocks are 795 MHz for the L4 and 700 MHz for the Rubin GPU. Boost clocks are 2040 MHz versus 2267 MHz. The L4 has 24 GB of GDDR6 memory on a 192-bit bus, delivering 300.1 GB/s of bandwidth. The Rubin GPU has 288 GB of HBM4 memory on a 16384-bit bus, delivering 22.1 TB/s. The memory clock is 1563 MHz with 12.5 Gbps effective for the L4, and 2695 MHz with 10.8 Gbps effective for the Rubin GPU.

Shading units number 7,424 on the L4 versus 28,720 on the Rubin GPU. Texture mapping units are 240 versus 896. Raster operations units are 80 versus 24. The L4 has 60 ray tracing cores and 240 tensor cores. The Rubin GPU has no recorded ray tracing cores and 896 tensor cores.

Pixel rate on the L4 is 163.2 GPixel/s, while the Rubin GPU manages 54.41 GPixel/s. Texture rate is 489.6 GTexel/s for the L4 and 2,031.2 GTexel/s for the Rubin GPU. FP32 throughput is 30.29 TFLOPS for the L4 and 130.0 TFLOPS for the Rubin GPU. FP16 throughput is 30.29 TFLOPS with a 1:1 ratio for the L4, and 260.0 TFLOPS with a 2:1 ratio for the Rubin GPU.

Power draw is starkly different. The L4 has a TDP of 72 W and requires a suggested PSU of 250 W. The Rubin GPU has a TDP of 2300 W and a suggested PSU of 2700 W. The L4 is single-slot with no power connectors; the Rubin GPU is an SXM Module. The L4 uses PCIe 4.0 x16, the Rubin GPU uses PCIe 6.0 x16. Both have no display outputs.

The L4 measures 169 mm in length and 56 mm in height. The Rubin GPU has no recorded dimensions. The L4 was released on 2023-03-20; the Rubin GPU's release date is recorded as 2025-12-31. The L4's production status is Active, as is the Rubin GPU's.

FAQ

Q: Does the L4 have any recorded benchmark advantages over the Rubin GPU?

A: Yes. The L4 has a Geekbench OpenCL score of 140,838 and a Geekbench Vulkan score of 121,306, with an average benchmark score of 131,072. The Rubin GPU has an average benchmark score of 0 and no recorded benchmark entries.

Q: How does the L4 compare to its nearest rivals in the database?

A: The L4 trails the NVIDIA GeForce RTX 3090 Ti by 0.7% in average score, sits 3.1% behind the NVIDIA RTX 4000 Ada Generation, 3.1% behind the NVIDIA A10M, and 3.2% behind the AMD Radeon PRO W6800.

Q: What memory configurations do the two devices use?

A: The L4 uses 24 GB of GDDR6 on a 192-bit bus with 300.1 GB/s bandwidth. The Rubin GPU uses 288 GB of HBM4 on a 16384-bit bus with 22.1 TB/s bandwidth.

Q: Which device has higher FP32 compute throughput?

A: The Rubin GPU delivers 130.0 TFLOPS FP32, compared to the L4's 30.29 TFLOPS FP32.

Q: What graphics APIs do the two devices support?

A: The L4 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The Rubin GPU lists N/A for DirectX, OpenGL, and Vulkan.

Q: What is the power requirement difference between the two?

A: The L4 has a TDP of 72 W with a suggested PSU of 250 W. The Rubin GPU has a TDP of 2300 W and a suggested PSU of 2700 W.

The Verdict

The data supports a clear verdict based on what can be measured. The L4 is a functional, verified accelerator with a 95th percentile ranking, a 131,072 average benchmark score, and a narrow performance gap of under 1% to 3.2% against a cluster of well-known rivals. It delivers 30.29 TFLOPS FP32, 24 GB of GDDR6 memory, and does so within a 72 W TDP in a single-slot form factor. Its API support includes DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, making it usable across a range of software stacks.

The Rubin GPU is a different class of hardware entirely. It has 130.0 TFLOPS FP32, 288 GB of HBM4 memory, 22.1 TB/s bandwidth, and a 2300 W TDP. Its transistor count of 336,000 million on a 1456 mm² die represents a massive investment in compute density. But the database contains no benchmark results for it, no nearest rivals, and no API compatibility. Its percentile ranking of 50 is the default median for unmeasured devices.

For buyers needing a server accelerator with recorded, comparable performance today, the L4 is the only choice supported by data. Its small deltas against the RTX 3090 Ti, RTX 4000 Ada Generation, A10M, and Radeon PRO W6800 show it competes effectively with much larger cards while drawing a fraction of their power.

For buyers planning a future deployment where the Rubin GPU's specifications become relevant, the decision must rest on paper specifications alone. The Rubin GPU offers over four times the FP32 throughput, twelve times the memory capacity, and over seventy times the memory bandwidth of the L4. Those are substantial advantages, but they are unverified in the database. The Rubin GPU also requires a 2700 W PSU and an SXM Module slot, which implies a completely different server infrastructure than the L4's low-power PCIe slot.

The verdict from the recorded data is unambiguous: the L4 is the proven performer, the Rubin GPU is the unproven specification sheet. Choose the L4 for measured results, choose the Rubin GPU only if the hardware specifications alone justify the deployment.