How fast will Gemma 4 31B feel on the Mac Studio M5 Ultra 256GB?

Gemma 4 31B on the Mac Studio M5 Ultra 256GB

Gemma 4 31B is a 31.27B-parameter model. At Q4_K_M it needs about 19.1 GB of memory. The Mac Studio M5 Ultra 256GB has 192 GB usable, so it fits entirely in memory. Expect about 35 tokens/sec (20–50), with the first token after 0.4 s for a short prompt. This estimate is interpolated from benchmarks of similar setups.

Speed by quantization

Quantization	File size	Memory	Generation	First token	Source
Q4_K_M	18.3 GB	Fits	35 tok/s	0.4 s	Derived
Q8_0	32.6 GB	Fits	20 tok/s	0.4 s	Derived
FP16	61.4 GB	Fits	10 tok/s	0.4 s	Derived

Gemma 4 31B on other hardware

H200 141GB (cloud) · 114 tok/s at Q4_K_M
H100 80GB (cloud) · 80 tok/s at Q4_K_M
NVIDIA RTX 5090 32GB · 43 tok/s at Q4_K_M
NVIDIA RTX PRO 6000 96GB · 43 tok/s at Q4_K_M
AMD Instinct MI50 32GB · 36 tok/s at Q4_K_M
AMD RX 7900 XTX 24GB · 34 tok/s at Q4_K_M
Mac Studio M5 Ultra 512GB · 31 tok/s at Q4_K_M
NVIDIA RTX 4090 24GB · 24 tok/s at Q4_K_M
Mac Studio M3 Ultra 512GB · 24 tok/s at Q4_K_M
AMD RX 7900 XT 20GB · 23 tok/s at Q4_K_M
AMD Radeon AI PRO R9700 32GB · 23 tok/s at Q4_K_M
NVIDIA RTX 3090 24GB · 22 tok/s at Q4_K_M
NVIDIA Tesla V100 32GB · 21 tok/s at Q4_K_M
MacBook Pro M5 Max 128GB · 18 tok/s at Q4_K_M
Mac Studio M4 Max 128GB · 16 tok/s at Q4_K_M
AMD Ryzen AI Max+ 395 128GB (Strix Halo) · 11 tok/s at Q4_K_M
AMD Ryzen AI Max+ PRO 495 192GB (Gorgon Halo) · 9.6 tok/s at Q4_K_M
Mac mini M5 Pro 64GB · 8.9 tok/s at Q4_K_M
MacBook Pro M5 Pro 48GB · 8.9 tok/s at Q4_K_M
AMD RX 9070 XT 16GB · 8.5 tok/s at Q4_K_M
NVIDIA RTX 5080 16GB · 8.5 tok/s at Q4_K_M
NVIDIA RTX 5070 Ti 16GB · 8.3 tok/s at Q4_K_M
NVIDIA RTX Spark N1X 128GB (laptop) · 7.1 tok/s at Q4_K_M
Intel Arc Pro B70 32GB · 6.9 tok/s at Q4_K_M
NVIDIA DGX Spark 128GB · 6.5 tok/s at Q4_K_M
NVIDIA RTX 5060 Ti 16GB · 6.4 tok/s at Q4_K_M
NVIDIA RTX 3060 12GB · 4.4 tok/s at Q4_K_M
CPU-only (Ryzen 9 9950X, 96GB DDR5) · 3.3 tok/s at Q4_K_M
MacBook M4 Pro 24GB · won't run

Other models on the Mac Studio M5 Ultra 256GB

Qwen 3.6/3.8 27B · 47 tok/s at Q4_K_M
Qwen 3.8 Flash-Next · 161 tok/s at Q4_K_M
GLM-5.3 Flash · 63 tok/s at Q4_K
Gemma 4 26B A4B · 257 tok/s at Q4_K_M
GPT-OSS 20B · 307 tok/s at MXFP4
Qwen 3.5/3.6 35B A3B · 347 tok/s at Q4_K_M
Qwen 3.5 9B · 113 tok/s at Q4_K_M
DeepSeek V4 Flash · 97 tok/s at UD-Q4_K_XL
DeepSeek V4.1 Flash · won't run
GPT-OSS 120B · 111 tok/s at MXFP4
Llama 3.1 8B · 130 tok/s at Q4_K_M
Gemma 4 12B · 90 tok/s at Q4_K_M
GLM-5.3 · won't run
Nemotron 3.5 Lightning 30B A3B · 267 tok/s at Q4_K_M

All models on the Mac Studio M5 Ultra 256GB · Gemma 4 31B on all hardware

Estimates for a short prompt on a single device. Measured numbers come from community benchmarks (r/LocalLLaMA, localscore.ai and more); others are derived from similar setups or projected from specs. Open source on GitHub.