NVIDIA GeForce RTX 4090 24GB vs NVIDIA L40S 48GB

The L40S is the newer part: Ada Lovelace, launched in 2023, against the GeForce RTX 4090's Ada Lovelace from 2022. Newer architectures typically add lower-precision formats and better throughput per watt, so check the precision rows your workload actually uses.

Dense throughput for the GeForce RTX 4090 against the L40S: FP64 1.3 vs 1.4 TFLOPS, FP32 83 vs 92 TFLOPS, FP16 165 vs 362 TFLOPS, FP8 330 vs 733 TFLOPS. Sparse figures, where the vendor publishes them, appear under each dense number in the performance table.

Memory is 24 GB against 48 GB, fed at 1.0 TB/s versus 864 GB/s. More memory per GPU means larger models fit before you have to shard across cards, which often matters more than raw TFLOPS for inference.

Power budgets are 450 W for the GeForce RTX 4090 and 350 W for the L40S. At FP32 that works out to 0.18 against 0.26 TFLOPS per watt.

For LLM training and inference, weight the FP8 and FP16 rows and memory capacity most heavily. For scientific and HPC workloads, the FP64 row is the one to read.