llamaperf

M4 16GB vs AMD RX 6700 XT for local LLMs

7 reports on the M4 16GB and 4 on the AMD RX 6700 XT

Which is faster for local LLMs?

On Qwen3 8B at 4-bit, the M4 16GB has 10.0 generation tokens/s (one run); the AMD RX 6700 XT has 61.0 generation tokens/s (one run); prompt processing 851.0 tokens/s (one run). 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 3.2x higher on the AMD RX 6700 XT (120 GB/s on the M4 16GB, 384 on the AMD RX 6700 XT).

M4 16GB
Memory
16GB unified
Memory bandwidth
120 GB/s
FP16 compute
4.3 TFLOPS
Reports
7
AMD RX 6700 XT
Memory
12GB
Memory bandwidth
384 GB/s
FP16 compute
26.4 TFLOPS
Reports
4

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

ModelM4 16GBAMD RX 6700 XT
Qwen3 8B4-bit10.0one runMLXcontext not stated61.0one runPP 851.0 (one run)llama.cppcontext 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.

ModelM4 16GBAMD RX 6700 XT
Qwen3 8B26.1 t/sQ3_K_M60.3 t/sQ3_K_M
Qwen3.8 27Bdoesn't fit at these settings1.6 t/sQ8_0, layers on CPU
Qwen3.8 125B · 6B activedoesn't fit at these settingsdoesn'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 activedoesn't fit at these settings13.3 t/sQ6_K, experts in RAM
Qwen3.6 27Bdoesn't fit at these settings1.6 t/sQ8_0, layers on CPU
Gemma 4 26B · 4B activedoesn't fit at these settings62.7 t/sQ2_K

Change the context, RAM or model in the calculator: M4 16GB · AMD RX 6700 XT

Every report on each card, with its source: M4 16GB · AMD RX 6700 XT

More comparisons