M5 Max 128GB vs AMD RX 7900 XTX for local LLMs
49 reports on the M5 Max 128GB and 47 on the AMD RX 7900 XTX
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 1.6x higher on the AMD RX 7900 XTX (614 GB/s on the M5 Max 128GB, 960 on the AMD RX 7900 XTX). The estimates below compare them on the models people run most.
M5 Max 128GB
- Memory
- 128GB unified
- Memory bandwidth
- 614 GB/s
- FP16 compute
- not on record
- Reports
- 49
AMD RX 7900 XTX
- Memory
- 24GB
- Memory bandwidth
- 960 GB/s
- FP16 compute
- 123 TFLOPS
- Reports
- 47
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.
| Model | M5 Max 128GB | AMD RX 7900 XTX |
|---|---|---|
| Qwen3.8 27B | 9.0 t/sFP16 | 34.8 t/sQ4_K_M |
| Qwen3.8 125B · 6B active | 41.2 t/sQ5_K_S | 19.5 t/sQ2_K, experts in RAM |
| Qwen3.6 35B · 3B active | 28.5 t/sFP16 | 123.2 t/sQ4_K_S |
| DeepSeek V4 Flash 284B · 13B active | 64.8 t/sQ2_K | doesn't fit at these settings |
| Qwen3.6 27B | 9.0 t/sFP16 | 34.8 t/sQ4_K_M |
| Gemma 4 26B · 4B active | 24.4 t/sFP16 | 78.4 t/sQ5_K_S |
Change the context, RAM or model in the calculator: M5 Max 128GB · AMD RX 7900 XTX
Every report on each card, with its source: M5 Max 128GB · AMD RX 7900 XTX