How fast will DeepSeek V4 Flash feel on the CPU-only (Ryzen 9 9950X, 96GB DDR5)?

DeepSeek V4 Flash on the CPU-only (Ryzen 9 9950X, 96GB DDR5)

DeepSeek V4 Flash is a 304.18B-parameter mixture-of-experts model (13B active per token). At UD-IQ1_M it needs about 87.7 GB of memory. The CPU-only (Ryzen 9 9950X, 96GB DDR5) has 89 GB usable, so it fits entirely in memory. Expect about 15 tokens/sec (13–17), with the first token after 0.6 s for a short prompt. This estimate is interpolated from benchmarks of similar setups.

Speed by quantization

QuantizationFile sizeMemoryGenerationFirst tokenSource
UD-IQ1_S82.5 GBFits15 tok/s0.6 sDerived
UD-IQ1_M86.9 GBFits15 tok/s0.6 sDerived
UD-IQ2_XXS90.9 GBPartial offload19 tok/s1.8 sProjected
UD-IQ2_M90.9 GBPartial offload19 tok/s1.8 sProjected
UD-Q2_K_XL96.8 GBPartial offload18 tok/s1.8 sProjected
UD-IQ3_XXS104.2 GBPartial offload16 tok/s1.8 sProjected
UD-IQ3_S116.1 GBPartial offload14 tok/s1.8 sProjected
UD-Q3_K_M128.1 GBPartial offload13 tok/s1.8 sProjected
UD-Q3_K_XL128.2 GBPartial offload13 tok/s1.8 sProjected
UD-IQ4_XS136.7 GBPartial offload12 tok/s1.8 sProjected
UD-IQ4_NL136.7 GBPartial offload12 tok/s1.8 sProjected
UD-Q4_K_XL155.1 GBPartial offload10 tok/s1.8 sProjected
UD-Q8_K_XL161.9 GBPartial offload9.9 tok/s1.8 sProjected

DeepSeek V4 Flash on other hardware

Other models on the CPU-only (Ryzen 9 9950X, 96GB DDR5)

All models on the CPU-only (Ryzen 9 9950X, 96GB DDR5) · 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.