llamaperf

NVIDIA A800 80GB vs NVIDIA RTX 3090 for local LLMs

0 reports on the NVIDIA A800 80GB and 218 on the NVIDIA RTX 3090

Which is faster for local LLMs?

Nobody has reported the same model at the same quant on both cards yet, so there's no measured head-to-head. Memory bandwidth, which caps how fast a card can write, is 2.1x higher on the NVIDIA A800 80GB (1,935 GB/s on the NVIDIA A800 80GB, 936 on the NVIDIA RTX 3090). The estimates below compare them on the models people run most.

NVIDIA A800 80GB
Memory
80GB
Memory bandwidth
1,935 GB/s
FP16 compute
312 TFLOPS
Reports
0
NVIDIA RTX 3090
Memory
24GB
Memory bandwidth
936 GB/s
FP16 compute
142 TFLOPS
Reports
218

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.

ModelNVIDIA A800 80GBNVIDIA RTX 3090
Qwen3.8 27B19.7 t/sFP1633.9 t/sQ4_K_M
Qwen3.8 125B · 6B active116.7 t/sQ4_K_S19.4 t/sQ2_K, experts in RAM
Qwen3.6 35B · 3B active141.9 t/sQ8_0120.1 t/sQ4_K_S
DeepSeek V4 Flash 284B · 13B active9.4 t/sQ2_K, experts in RAMdoesn't fit at these settings
Qwen3.6 27B19.7 t/sFP1633.9 t/sQ4_K_M
Gemma 4 26B · 4B active50.7 t/sFP1676.4 t/sQ5_K_S

Change the context, RAM or model in the calculator: NVIDIA A800 80GB · NVIDIA RTX 3090

Every report on each card, with its source: NVIDIA A800 80GB · NVIDIA RTX 3090

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