Stable Diffusion 3.5 Large on Apple M4 Ultra (192GB)
Yes — M4 Ultra (192GB) handles Stable Diffusion 3.5 Large well at FP16 — ~7s first response. Solid daily-driver performance on 192 GB VRAM.
Model Size
8.1B
Device VRAM
192 GB
Bandwidth
819 GB/s
Quantization
FP16
Performance by Quantization
OwnRig currently has one published compatibility entry for Stable Diffusion 3.5 Large on Apple M4 Ultra (192GB) at FP16. This is the best supported pairing we can stand behind today.
| Quantization | Speed | TTFT | Fits in VRAM | Rating | Confidence |
|---|---|---|---|---|---|
| FP16 | – | 6667ms | ✓ Yes | Good | estimated |
Notes
FP16
M4 Ultra: ~1.5x M4 Max performance due to higher memory bandwidth and GPU cores.
About Stable Diffusion 3.5 Large
Stable Diffusion 3.5 Large (8.1B) is a image gen model. Latest Stable Diffusion architecture with significantly improved prompt adherence, typography, and composition over SDXL. Higher VRAM requirement (12GB+ at FP16) but produces noticeably better images. The current standard for local image generation.
View all Stable Diffusion 3.5 Large hardware options →About Apple M4 Ultra (192GB)
Apple M4 Ultra (192GB) has 192 GB at 819 GB/s. Available in Mac Studio, Mac Pro.
See all models Apple M4 Ultra (192GB) can run →Estimate method: Estimated from M4 Max benchmarks scaled by memory bandwidth ratio (819/546 GB/s). Reference hardware source: github.com (2026-03-14)
Performance varies by driver version, inference engine, quantization method, context length, and system configuration. Figures shown are estimates based on community benchmarks and may not reflect your exact setup. Product names are trademarks of their respective owners. OwnRig is independent and not affiliated with any hardware or AI model provider.