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locuslabPhiPhiForCausalLM

Tofu Ft Phi 1.5 — Hardware Requirements & GPU Compatibility

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Tofu Ft Phi 1.5 is a 1.4B-parameter open language model from locuslab in the Phi family. It supports a context window of up to 2,048 tokens. At Q4_K_M it needs about 1.55 GB of VRAM — see which GPUs and Macs can run it below.

1.4B params · dense2K contextApache 2.045.7K downloads1 likes
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Runs great on a 24 GB GPU

Runs from8 GB Q4_K_M · 2KBest on24 GB Q4_K_M · ~423 tok/s · 2KMacs from8 GB Q4_K_M · ~46 tok/s

Apache 2.0

Reference GPU · RTX 4090 24 GB

Estimates, ±20% · how we estimate

Run Tofu Ft Phi 1.5

One recommended way. Every other method, OS and quant is in the step-by-step guide.Each way opens a step-by-step guide for your OS and quant.

Recommended

vLLM
one command · needs vLLM installed
$vllm serve locuslab/tofu_ft_phi-1.5 --max-model-len 2048

vLLM repo with its own quantisation

Download: Weights on Hugging Face

install, OS, other quants

Ways to runOther ways

each opens step-by-step

Run in cloud

Runs on RTX 3080 Ti (12 GB) (10 GB headroom) · Q4_K_M

Generation speed
~383 tok/s
generation speed
Cost per 1M output tokens
$0.089
per 1M output tokens

How Much VRAM Does Tofu Ft Phi 1.5 Need?

Select a quantization level; the listed hardware adheres to it.

QuantizationVRAM+32KOn RTX 4090 (reference)
1.3 GB—2-bit · K-quant — 2-bit quantization with K-quant improvementsFits: 2K context · ~500 tok/s
1.4 GB—3-bit medium — 3-bit medium quantizationFits: 2K context · ~471 tok/s
1.6 GB—4-bit medium — 4-bit medium quantization — most popular sweet spotFits: 2K context · ~423 tok/s
1.7 GB—5-bit medium — 5-bit medium quantization — good quality/size tradeoffFits: 2K context · ~383 tok/s
1.9 GB—6-bit, very good — 6-bit quantization, very good qualityFits: 2K context · ~350 tok/s
2.1 GB—8-bit, near-lossless — 8-bit quantization, near-losslessFits: 2K context · ~309 tok/s
3.5 GB—16-bit · bfloat — Brain floating point 16 — preferred for trainingFits: 2K context · ~185 tok/s
est.calculated, no published file yet

Selected Q4_K_M

4-bit medium quantization

1.6GBat 2K context

Weights
0.9 GB
KV cache
0.4 GB
Overhead
0.3 GB

Fits RTX 4090 (reference) · 22.5 GB free · ~423 tok/s

≥50 tok/s needs ≥119 GB/s · RTX 5090 ~752, RTX 3090 Ti ~423

Which Hardware Can Run Tofu Ft Phi 1.5?

Q4_K_M · 1.6 GB

Tofu Ft Phi 1.5 (Q4_K_M) requires 1.6 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 3+ GB is recommended. 52 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti. 163 devices with unified memory can run Tofu Ft Phi 1.5, including Mac Studio (M3 Ultra, 256GB), Mac Studio (M3 Ultra, 512GB).

By VRAM tier · typical GPUs and Macs at Q4_K_M
8 GB · RTX 4060Q4_K_M · 1.6 GB · ~114 tok/s · 2K8 GB tier →
12 GB · RTX 3060 12GBQ4_K_M · 1.6 GB · ~151 tok/s · 2K12 GB tier →
16 GB · RTX 5060 Ti 16GBQ4_K_M · 1.6 GB · ~188 tok/s · 2K16 GB tier →
24 GB · RTX 4090referenceQ4_K_M · 1.6 GB · ~423 tok/s · 2K24 GB tier →
Mac 32 GB · Mac Mini M4Q4_K_M · 1.6 GB · ~54 tok/s · 2KMacs →
Mac 64 GB · Mac Studio M4 MaxQ4_K_M · 1.6 GB · ~247 tok/s · 2KMacs →

Alternatives to Tofu Ft Phi 1.5

Phi family · 9 models →

Similar models

6
ModelScoreVRAMtok/sWhy it is similar
Inkling Small DSpark PreviewRadixArk—1.5 GB~555same size
Sweep Next Edit 1.5BXenova—1.6 GB~551same size
Ouro 1.4BByteDance—6.4 GB~184same size
OLMo 2 0425 1B InstructAllen AI—1.7 GB~449same size
Granite 3.0 1B A400m InstructIBM—1.3 GB~524same size
Transformer 1.3B 100Bfla-hub—3 GB~218same size

Specifications

Publisher
locuslab
Family
Phi
Parameters
1.4B
Architecture
PhiForCausalLM
Context Length
2,048 tokens
Vocabulary Size
51,200
Release Date
2024-01-31
License
Apache 2.0

Frequently Asked Questions

How much VRAM does Tofu Ft Phi 1.5 need?

Tofu Ft Phi 1.5 requires 1.6 GB of VRAM at Q4_K_M, or 3.5 GB at BF16.

VRAM = Weights + KV Cache + Overhead

Weights = 1.4B × 4.8 bits ÷ 8 = 0.9 GB

KV Cache + Overhead ≈ 0.7 GB (at 2K context + ~0.3 GB framework)

Fit ratings and hardware model lists check this model with room for a 16K-token context, which needs a little more memory.

VRAM usage by quantization

1.6 GB

Learn more about VRAM estimation →

What's the best quantization for Tofu Ft Phi 1.5?

For Tofu Ft Phi 1.5, Q4_K_M (1.6 GB) offers the best balance of quality and VRAM usage. Q5_K_M (1.7 GB) provides better quality if you have the VRAM. The smallest option is Q2_K at 1.3 GB.

VRAM requirement by quantization

Q2_K
1.3 GB
Q4_K_M ★
1.6 GB
Q5_K_M
1.7 GB
Q6_K
1.9 GB
Q8_0
2.1 GB
BF16
3.5 GB

★ Recommended — best balance of quality and VRAM usage.

Learn more about quantization →

Can I run Tofu Ft Phi 1.5 on a Mac?

Yes — MacBook Air 13" M3 (8 GB) and 145 other Macs can run Tofu Ft Phi 1.5. Apple Silicon uses unified memory, so the model shares RAM with the system. At Q4_K_M you need at least 1.6 GB of usable unified memory (RAM minus macOS overhead).

Can I run Tofu Ft Phi 1.5 locally?

Yes — Tofu Ft Phi 1.5 can run locally on consumer hardware. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Tofu Ft Phi 1.5?

At Q4_K_M, Tofu Ft Phi 1.5 can reach ~3097 tok/s on AMD Instinct MI350X. On NVIDIA GeForce RTX 4090: ~423 tok/s. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.

tok/s = (bandwidth GB/s ÷ model GB) × efficiency

Example: NVIDIA B200 → 8000 ÷ 1.55 × 0.65 = ~3355 tok/s

Estimated speed at Q4_K_M (1.6 GB)

~3355 tok/s
~423 tok/s
~3355 tok/s
~3097 tok/s

Real-world results typically within ±20%. Speed depends on batch size, quantization kernel, and software stack.

Learn more about tok/s estimation →

What's the download size of Tofu Ft Phi 1.5?

At Q4_K_M, the download is about 0.85 GB. The full-precision BF16 version is 2.84 GB. The smallest option (Q2_K) is 0.60 GB.

Which GPUs can run Tofu Ft Phi 1.5?

52 consumer GPUs can run Tofu Ft Phi 1.5 at Q4_K_M. Top options include AMD Radeon RX 6700 XT, AMD Radeon RX 6800, AMD Radeon RX 6800 XT. 52 GPUs have plenty of headroom for comfortable inference.

Which devices can run Tofu Ft Phi 1.5?

163 devices with unified memory can run Tofu Ft Phi 1.5 at Q4_K_M (1.6 GB), including AMD Ryzen AI 9 HX 370 (Strix Point) Laptop, ASUS Ascent GX10, Beelink GTR9 Pro (Ryzen AI Max+ 395, 128 GB), Framework Desktop (Ryzen AI Max+ 395, 128 GB). Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.