llamaperf

M4 Max 64GB vs AMD RX 7900 XTX for local LLMs

18 reports on the M4 Max 64GB and 46 on the AMD RX 7900 XTX

Which is faster for local LLMs?

On Qwen3.8 27B at 4-bit, the M4 Max 64GB has 23.9 generation tokens/s (one run); prompt processing 119.9 tokens/s (one run); the AMD RX 7900 XTX has 42.5 generation tokens/s (6 runs); prompt processing 640.0 tokens/s (4 runs). 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 1.8x higher on the AMD RX 7900 XTX (546 GB/s on the M4 Max 64GB, 960 on the AMD RX 7900 XTX). Across 4 shared models with generation measurements on both cards, the M4 Max 64GB's median is higher on 0 and the AMD RX 7900 XTX's on 4.

M4 Max 64GB
Memory
64GB unified
Memory bandwidth
546 GB/s
FP16 compute
18.4 TFLOPS
Reports
18
AMD RX 7900 XTX
Memory
24GB
Memory bandwidth
960 GB/s
FP16 compute
123 TFLOPS
Reports
46

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 Max 64GBAMD RX 7900 XTX
Qwen3.8 27B4-bit23.9one runPP 119.9 (one run)llama.cppcontext not stated42.56 runsPP 640.0 (4 runs)llama.cpp, Ollama, 2 not stated64K to 220K context, 3 not stated
Gemma 4 31B4-bit22.4one runPP 62.7 (one run)llama.cppcontext not stated30.1one runPP 422.3 (one run)llama.cpp32K context
Gemma 4 26B · 4B active4-bit81.7one runPP 379.6 (one run)llama.cppcontext not stated142.8one runPP 4331.2 (one run)llama.cppcontext not stated
Qwen3.6 35B · 3B active4-bit76.4one runPP 319.9 (one run)llama.cppcontext not stated125.5one runPP 1874.7 (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 Max 64GBAMD RX 7900 XTX
Qwen3.8 27B13.5 t/sQ8_034.8 t/sQ4_K_M
Gemma 4 31B11.8 t/sQ8_034.1 t/sQ4_K_S
Gemma 4 26B · 4B active36.4 t/sQ8_078.4 t/sQ5_K_S
Qwen3.6 35B · 3B active42.5 t/sQ8_0123.2 t/sQ4_K_S
Qwen3.8 125B · 6B active61.4 t/sQ2_K19.5 t/sQ2_K, experts in RAM
DeepSeek V4 Flash 284B · 13B activedoesn't fit at these settingsdoesn't fit at these settings
Qwen3.6 27B13.5 t/sQ8_034.8 t/sQ4_K_M
DeepSeek V4.1 Flash 552B · 16B activedoesn't fit at these settingsdoesn't fit at these settings
GLM-5.3 320B · 18B activedoesn't fit at these settingsdoesn't fit at these settings
Qwen3.5 9B20.2 t/sFP1658.7 t/sQ8_0

Change the context, RAM or model in the calculator: M4 Max 64GB · AMD RX 7900 XTX

Every report on each card, with its source: M4 Max 64GB · AMD RX 7900 XTX

More comparisons