Intel Arc B580 12GB vs M4 Max 128GB for local LLMs
10 reports on the Intel Arc B580 12GB and 52 on the M4 Max 128GB
Which is faster for local LLMs?
On Qwen3.8 27B at 2-bit, the Intel Arc B580 12GB has 0.7 generation tokens/s (one run); the M4 Max 128GB has 24.5 generation tokens/s (2 runs); prompt processing 251.4 tokens/s (2 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 20% higher on the M4 Max 128GB (456 GB/s on the Intel Arc B580 12GB, 546 on the M4 Max 128GB).
- Memory
- 12GB
- Memory bandwidth
- 456 GB/s
- FP16 compute
- 117 TFLOPS
- Reports
- 10
- Memory
- 128GB unified
- Memory bandwidth
- 546 GB/s
- FP16 compute
- 18.4 TFLOPS
- Reports
- 52
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
| Model | Intel Arc B580 12GB | M4 Max 128GB |
|---|---|---|
| Qwen3.8 27B2-bit | 0.7one runFreeToken128 context | 24.52 runsPP 251.4 (2 runs)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.
| Model | Intel Arc B580 12GB | M4 Max 128GB |
|---|---|---|
| Qwen3.8 27B | 1.6 t/sQ8_0, layers on CPU | 6.7 t/sFP16 |
| Qwen3.8 125B · 6B active | doesn't fit at these settings | 30.7 t/sQ5_K_S |
| Qwen3.6 35B · 3B active | 13.7 t/sQ6_K, experts in RAM | 21.2 t/sFP16 |
| DeepSeek V4 Flash 284B · 13B active | doesn't fit at these settings | 48.3 t/sQ2_K |
| Qwen3.6 27B | 1.6 t/sQ8_0, layers on CPU | 6.7 t/sFP16 |
| Gemma 4 26B · 4B active | 74.5 t/sQ2_K | 18.2 t/sFP16 |
| DeepSeek V4.1 Flash 552B · 16B active | doesn't fit at these settings | doesn't fit at these settings |
Change the context, RAM or model in the calculator: Intel Arc B580 12GB · M4 Max 128GB
Every report on each card, with its source: Intel Arc B580 12GB · M4 Max 128GB