NVIDIA GeForce RTX 3080 12GB vs NVIDIA GeForce RTX 3090 Ti 24GB

Both GPUs launched in 2022: the GeForce RTX 3080 on Ampere and the GeForce RTX 3090 Ti on Ampere.

Dense throughput for the GeForce RTX 3080 against the GeForce RTX 3090 Ti: FP64 0.5 vs 0.6 TFLOPS, FP32 31 vs 40 TFLOPS, FP16 61 vs 40 TFLOPS. Sparse figures, where the vendor publishes them, appear under each dense number in the performance table.

Memory is 12 GB against 24 GB. 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 350 W for the GeForce RTX 3080 and 450 W for the GeForce RTX 3090 Ti. At FP32 that works out to 0.09 against 0.09 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.