llamaperf

NVIDIA RTX 3090 vs AMD RX 6700 for local LLMs

165 reports on the NVIDIA RTX 3090 and 0 on the AMD RX 6700

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 2.9x higher on the NVIDIA RTX 3090 (936 GB/s on the NVIDIA RTX 3090, 320 on the AMD RX 6700). The estimates below compare them on the models people run most.

NVIDIA RTX 3090
Memory
24GB
Memory bandwidth
936 GB/s
FP16 compute
142 TFLOPS
Reports
165
AMD RX 6700
Memory
10GB
Memory bandwidth
320 GB/s
FP16 compute
22.6 TFLOPS
Reports
0

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 RTX 3090AMD RX 6700
Qwen3.8 27B33.9 t/sQ4_K_M1.8 t/sQ6_K, layers on CPU
Qwen3.8 125B · 6B active19.4 t/sQ2_K, experts in RAMdoesn't fit at these settings
DeepSeek V4 Flash 284B · 13B activedoesn't fit at these settingsdoesn't fit at these settings
Qwen3.6 35B · 3B active120.1 t/sQ4_K_S15.1 t/sQ5_K_M, experts in RAM
Qwen3.6 27B33.9 t/sQ4_K_M1.8 t/sQ6_K, layers on CPU
Gemma 4 26B · 4B active76.4 t/sQ5_K_S7.8 t/sQ8_0, experts in RAM

Change the context, RAM or model in the calculator: NVIDIA RTX 3090 · AMD RX 6700

Every report on each card, with its source: NVIDIA RTX 3090 · AMD RX 6700

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