willitrun·ai

Can Phi 3.5 Mini 4B run on RTX 5080 16GB?

YES — Runs Great

A71Great
Estimated from fit model

Phi 3.5 Mini 4B needs ~10.8 GB VRAM. RTX 5080 16GB has 16.0 GB. With Q4_K_M quantization, expect ~76 tok/s.

Runtime: llama.cppCapacity: RoomyBandwidth: HighStack: StandardBottleneck: Balanced
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Operating mode

Choose the run profile you care about

Interactive favors responsiveness, while light API and scale-out lean harder on serving readiness. The fit stays the same, but the recommendation lens changes.

Current mode

Balanced

Balanced for general local use. Keeps the ranking neutral across personal and serving workflows.

Capabilities:

Select quantization to explore

Q4_K_M (Medium quality) 10.8 GB, 76.0 tok/s, Runs well
10.8 GB required16.0 GB available
68% VRAM used

Fit status

Runs well

Decode

76.0 tok/s

TTFT

2547 ms

Safe context

30K

Memory

10.8 GB / 16.0 GB

Memory breakdown

Weights2.4 GB
KV Cache5.9 GB
Runtime0.9 GB
Headroom1.6 GB

See how fast it feels

See how fast it feelsPhi 3.5 Mini 4B on RTX 5080 16GB
1st promptCold start — includes initialization
>What is local AI inference?
Local AI inference means running an AI language model directly on your own hardware — your laptop, desktop, or server — instead of sending requests to a remote cloud API. When you run inference locally the model weights are loaded into your GPU or unified memory. Each token you generate requires reading those weights from memory, so memory bandwidth is the main bottleneck for decode speed. Key benefits of running locally: - Full privacy: your prompts never leave your machine - No per-token cost or rate limits - Works offline once the model is downloaded - Latency depends only on your hardware
2nd promptWarm — model ready, no init overhead
>How much VRAM do I need?
It depends on the model size and quantization level. A rough rule of thumb: Model size Q4 (4-bit) Q8 (8-bit) FP16 7B params ~4.3 GB ~7.5 GB ~14 GB 13B params ~7.9 GB ~13.9 GB ~26 GB 70B params ~42.7 GB ~74.9 GB ~140 GB Most people use 4-bit quantization (Q4_K_M) which gives 90-95% of full quality at a fraction of the memory. A 24 GB GPU can comfortably run most 7B-13B models.
Estimated: 76.0 tok/s decode · 2.5s TTFT (warm) · 190 tok/s prefill

What limits this setup

This setup is broadly balanced for this model.

No major red flags

This recommendation has enough memory headroom and acceptable estimated speed for the selected workload.

Best improvement path

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatBRuns well76.0 tok/s1389 ms30K
CodingARuns well76.0 tok/s2547 ms30K
Agentic CodingBRuns with offload (needs ~0.1 GB host RAM)76.0 tok/s3705 ms30K
ReasoningARuns well76.0 tok/s3011 ms30K
RAGBRuns with offload (needs ~0.1 GB host RAM)76.0 tok/s4632 ms30K

Inference speed

Phi 3.5 Mini 4B inference speed — tokens per second by GPU & Mac

Estimated decode speed (tokens/sec) for Phi 3.5 Mini 4B at Q4_K_M across popular GPUs and Apple Silicon, using the fastest local runtime per device. Fastest is RTX 5090 32GB at ~76 tok/s. Speed is memory-bandwidth bound, so cards that fit the whole model in VRAM run far faster than ones that offload to system RAM.

GPU / MacMemoryQuantSpeed (tok/s)Fits?
NVIDIARTX 5090 32GB
32 GBQ4_K_M76.0Fits
NVIDIARTX 4090 24GB
24 GBQ4_K_M64.0Fits
NVIDIARTX 4080 Super 16GB
16 GBQ4_K_M64.0Fits
NVIDIARTX 4070 12GB
12 GBQ4_K_M64.0Tight
NVIDIARTX 3090 24GB
24 GBQ4_K_M56.0Fits
NVIDIARTX 3060 12GB
12 GBQ4_K_M56.0Tight
RX 7900 XTX 24GB
24 GBQ4_K_M56.0Fits
MacBook Pro M4 Max 128GB
128 GBQ4_K_M56.0Fits
Mac Studio M3 Ultra 256GB
256 GBQ4_K_M56.0Fits
Mac Studio M2 Ultra 128GB
128 GBQ4_K_M56.0Fits
Mac Studio M1 Ultra 128GB
128 GBQ4_K_M56.0Fits
MacBook Pro M4 Max 64GB
64 GBQ4_K_M56.0Fits
MacBook Pro M3 Max 64GB
64 GBQ4_K_M56.0Fits
MacBook Pro M1 Max 64GB
64 GBQ4_K_M56.0Fits
MacBook Pro M4 Pro 48GB
48 GBQ4_K_M56.0Fits
NVIDIARTX 4060 8GB
8 GBQ4_K_M35.9Too big

Estimates for single-stream decoding at Q4_K_M; real tokens/sec varies with prompt length, context, batch size, and runtime build. Prompt processing (prefill) is faster than the decode figures shown here.

Quantization options

How Phi 3.5 Mini 4B (4B params) fits at each quantization level on RTX 5080 16GB (16.0 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
1.6 GB
LowB62
Q3_K_S
3
2.0 GB
LowB62
NVFP4
4
2.2 GB
MediumB62
Q4_K_M
4
2.4 GB
MediumB62
Q5_K_M
5
2.9 GB
HighB63
Q6_K
6
3.3 GB
HighB63
Q8_0
8
4.3 GB
Very HighB64
F16Best for your GPU
16
8.2 GB
MaximumB67

Get started

Copy-paste commands to run Phi 3.5 Mini 4B on your machine.

Run

ollama run phi3.5

Your hardware

More models your RTX 5080 16GB can run

ModelParamsGradeDecodeCapabilities
AlibabaQwen 3.5 9B9BS122.2 tok/s
AlibabaQwen 3 14B14BS79.6 tok/s
AlibabaQwen 3 8B8BS137.5 tok/s
MicrosoftPhi-4-reasoning-plus 14B14.7BS71.2 tok/s
OpenAIGPT-OSS 20B21BA66.7 tok/s

Frequently asked questions

Can RTX 5080 16GB run Phi 3.5 Mini 4B?

Yes, RTX 5080 16GB can run Phi 3.5 Mini 4B with a A grade (Runs well). Expected decode speed: 76.0 tok/s.

How much VRAM does Phi 3.5 Mini 4B need?

Phi 3.5 Mini 4B (4B parameters) requires approximately 10.8 GB of memory with Q4_K_M quantization.

What is the best quantization for Phi 3.5 Mini 4B?

The recommended quantization for Phi 3.5 Mini 4B is Q4_K_M, which balances quality and memory efficiency.

What speed will Phi 3.5 Mini 4B run at on RTX 5080 16GB?

On RTX 5080 16GB, Phi 3.5 Mini 4B achieves approximately 76.0 tokens per second decode speed with a time-to-first-token of 2547ms using Q4_K_M quantization.

Can RTX 5080 16GB run Phi 3.5 Mini 4B for coding?

For coding workloads, Phi 3.5 Mini 4B on RTX 5080 16GB receives a A grade with 76.0 tok/s and 30K context.

What context window can Phi 3.5 Mini 4B use on RTX 5080 16GB?

On RTX 5080 16GB, Phi 3.5 Mini 4B can safely use up to 30K tokens of context. The model's official context limit is 128K, but available memory constrains the safe maximum.

See all results for RTX 5080 16GBSee all hardware for Phi 3.5 Mini 4B
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