llamaperf

NVIDIA L4 vs NVIDIA RTX 5090 for local LLMs

3 reports on the NVIDIA L4 and 169 on the NVIDIA RTX 5090

Which is faster for local LLMs?

On Qwen3.8 27B at 4-bit, the NVIDIA L4 has 14.6 generation tokens/s (one run); the NVIDIA RTX 5090 has 80.0 generation tokens/s (7 runs). Those are community reports whose engines and settings differ, so the gap is a rough sign, not a controlled measure of the two cards. Memory bandwidth, which caps how fast a card can write, is 6.0x higher on the NVIDIA RTX 5090 (300 GB/s on the NVIDIA L4, 1,792 on the NVIDIA RTX 5090).

NVIDIA L4
Memory
24GB
Memory bandwidth
300 GB/s
FP16 compute
121 TFLOPS
Reports
3
NVIDIA RTX 5090
Memory
32GB
Memory bandwidth
1,792 GB/s
FP16 compute
419 TFLOPS
Reports
169

Measured on both

Generation and prompt processing speeds from plain runs (one device, one request, no speculative decoding, the whole model in the device's memory) of the same model size at the same bit class. Each side shows the engines and reported context behind its median. Context can mean a configured window or prompt depth, so these are community comparisons with differing settings. How to read these

ModelNVIDIA L4NVIDIA RTX 5090
Qwen3.8 27B4-bit14.6one runllama.cppcontext not stated80.07 runsllama.cpp, TensorSharp +1, 2 not stated40K to 256K context, 2 not stated

Estimated by the calculator

The quant the calculator recommends for each card and its estimated speed at a 32,768-token context with 32 GB of system RAM, from memory bandwidth and the model's shape. Where a model was also measured above, the measurement wins.

ModelNVIDIA L4NVIDIA RTX 5090
Qwen3.8 27B10.9 t/sQ4_K_M44.9 t/sQ6_K
Qwen3.8 125B · 6B active16.4 t/sQ2_K, experts in RAM20.3 t/sQ2_K, experts in RAM
Qwen3.6 35B · 3B active38.5 t/sQ4_K_S163.0 t/sQ5_K_M
DeepSeek V4 Flash 284B · 13B activedoesn't fit at these settingsdoesn't fit at these settings
Qwen3.6 27B10.9 t/sQ4_K_M44.9 t/sQ6_K
Gemma 4 26B · 4B active24.5 t/sQ5_K_S114.5 t/sQ6_K
DeepSeek V4.1 Flash 552B · 16B activedoesn't fit at these settingsdoesn't fit at these settings

Change the context, RAM or model in the calculator: NVIDIA L4 · NVIDIA RTX 5090

Every report on each card, with its source: NVIDIA L4 · NVIDIA RTX 5090

More comparisons