How fast will DeepSeek V4 Flash feel on the Mac Studio M3 Ultra 512GB?

DeepSeek V4 Flash on the Mac Studio M3 Ultra 512GB

DeepSeek V4 Flash is a 304.18B-parameter mixture-of-experts model (13B active per token). At UD-Q4_K_XL it needs about 155.8 GB of memory. The Mac Studio M3 Ultra 512GB has 384 GB usable, so it fits entirely in memory. Expect about 29 tokens/sec (26–33), with the first token after 0.4 s for a short prompt. This estimate is based on community benchmarks of this exact setup.

Speed by quantization

QuantizationFile sizeMemoryGenerationFirst tokenSource
UD-IQ1_S82.5 GBFits114 tok/s0.4 sDerived
UD-IQ1_M86.9 GBFits112 tok/s0.4 sDerived
UD-IQ2_XXS90.9 GBFits110 tok/s0.4 sDerived
UD-IQ2_M90.9 GBFits36 tok/s0.4 sMeasured
UD-Q2_K_XL96.8 GBFits103 tok/s0.4 sDerived
UD-IQ3_XXS104.2 GBFits96 tok/s0.4 sDerived
UD-IQ3_S116.1 GBFits86 tok/s0.4 sDerived
UD-Q3_K_M128.1 GBFits78 tok/s0.4 sDerived
UD-Q3_K_XL128.2 GBFits78 tok/s0.4 sDerived
UD-IQ4_XS136.7 GBFits73 tok/s0.4 sDerived
UD-IQ4_NL136.7 GBFits73 tok/s0.4 sDerived
UD-Q4_K_XL155.1 GBFits29 tok/s0.4 sMeasured
UD-Q8_K_XL161.9 GBFits62 tok/s0.4 sDerived

DeepSeek V4 Flash on other hardware

Other models on the Mac Studio M3 Ultra 512GB

All models on the Mac Studio M3 Ultra 512GB · DeepSeek V4 Flash 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.