01.AI · Yi-1.5 · 34.4B parameters

Yi-1.5 34B VRAM requirements

Yi-1.5 34B has 60 layers and uses grouped-query attention (8 KV heads). At Q4_K_M the weights come to 19.5 GB, and the best quantisation that fits a 24 GB card is Q4_K_S.

Won't fit

22.2 GB of 21.8 GB · 102%
023 GB
Weights 19.5 GB
KV cache 1.9 GB
Runtime overhead 0.9 GB
Over the limit 0.5 GB

Short by 0.5 GB. You can run it with 58 of 60 layers on the RTX 4090 and the rest in system RAM, at roughly 19.7 tok/s — usable for batch work, painful for chat. A smaller quantisation or a shorter context is usually the better trade.

Generation19.7tok/s
Prompt processing1007tok/s
Max context6Ktokens
KV per 1K tokens0GB

Every quantisation of Yi-1.5 34B on a RTX 4090

Highlighted row is the highest quality that still fits at 8K context.

QuantisationbpwWeights TotalVerdictMax ctxtok/s
FP16 / BF16 16.00 64.1 GB 66.8 GB Won't fit 0.80
INT8 / W8A8 8.50 33.8 GB 36.6 GB Won't fit 2.27
Q8_0 (GGUF) 8.50 33.8 GB 36.6 GB Won't fit 2.27
FP8 (E4M3) 8.00 32.0 GB 34.8 GB Won't fit 2.56
Q6_K 6.56 26.3 GB 29.0 GB Won't fit 4.27
Q5_K_M 5.67 22.7 GB 25.5 GB Won't fit 7.36
Q5_K_S 5.52 22.1 GB 24.9 GB Won't fit 8.13
Q4_K_M 4.85 19.5 GB 22.2 GB Won't fit 6K 19.7
Q4_K_S 4.58 18.4 GB 21.2 GB Fits, but tight 10K 30.8
Q4_0 4.55 18.3 GB 21.1 GB Fits, but tight 11K 31.0
AWQ 4-bit 4.25 18.3 GB 21.0 GB Fits, but tight 11K 31.1
GPTQ 4-bit 4.25 18.3 GB 21.0 GB Fits, but tight 11K 31.1
MXFP4 4.25 18.3 GB 21.0 GB Fits, but tight 11K 31.1
IQ4_XS 4.25 17.2 GB 19.9 GB Fits, but tight 16K 33.0
Q3_K_M 3.91 15.8 GB 18.6 GB Runs comfortably 22K 35.6
IQ3_M 3.70 15.0 GB 17.8 GB Runs comfortably 25K 37.4
IQ3_XXS 3.06 12.5 GB 15.3 GB Runs comfortably 32K 44.2
Q2_K 2.63 10.8 GB 13.6 GB Runs comfortably 32K 50.4
IQ2_XXS 2.06 8.6 GB 11.4 GB Runs comfortably 32K 61.9
IQ1_M 1.75 7.4 GB 10.2 GB Runs comfortably 32K 70.6

Yi-1.5 34B on each GPU

Q4_K_M weights at 8K context, single card, monitor attached.

GPUVRAMGB/sVerdictMax ctxtok/s
H100 SXM 80GB 80 3350 Runs comfortably 32K 110
A100 80GB 80 2039 Runs comfortably 32K 61.1
RTX 5090 32 1792 Runs comfortably 32K 56.8
L40S 48 864 Runs comfortably 32K 25.1
RTX A6000 48 768 Runs comfortably 32K 23.3
Mac Studio M3 Ultra 256GB 256 819 Runs comfortably 32K 23.0
RTX 4090 24 1008 Won't fit 6K 19.7
RTX 3090 24 936 Won't fit 6K 19.6
Radeon RX 7900 XTX 24 960 Won't fit 6K 18.1
Mac Studio M4 Max 128GB 128 546 Runs comfortably 32K 17.1
NVIDIA DGX Spark (GB10) 128 273 Runs comfortably 32K 8.80
Mac Mini M4 Pro 48GB 48 273 Runs comfortably 32K 8.57
Ryzen AI Max+ 395 128GB 128 256 Runs comfortably 32K 6.57
RTX 5080 16 960 Won't fit 4.53
RTX 5070 Ti 16 896 Won't fit 4.50
RTX 5060 Ti 16GB 16 448 Won't fit 4.13
RTX 4080 Super 16 736 Won't fit 4.00
RTX 4070 Ti Super 16 672 Won't fit 3.96
RTX 4060 Ti 16GB 16 288 Won't fit 3.43
RTX 5070 12 672 Won't fit 3.16
RTX 3060 12GB 12 360 Won't fit 2.85
RTX 4070 Super 12 504 Won't fit 2.81
RTX 4070 12 504 Won't fit 2.81
RTX 3080 10GB 10 760 Won't fit 2.69
Arc B580 12 456 Won't fit 2.36

Architecture

Parameters34.4B
Layers60
Hidden size7168
Attention heads / KV heads56 / 8
Head dimension128
Vocabulary64,000
Trained context32K
KV cache per 1K tokens0 GB
Hugging Face01-ai/Yi-1.5-34B-Chat

The 01.AI family

Yi-1.5 34B lands in the awkward gap above 30B: 19.5 GB of weights at Q4_K_M, so a 24 GB card takes it only with a modest context.

huggingface.co/01-ai · 01.ai

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