Will It Run AI

Can Phi-4-reasoning-plus 14B run on RTX 4080 Laptop 12GB?

BARELY — Tight on Memory

A73Great
Estimated from fit model

Phi-4-reasoning-plus 14B needs ~14.1 GB VRAM. RTX 4080 Laptop 12GB has 12.0 GB. With Q4_K_M quantization, expect ~22 tok/s.

Runtime: llama.cppCapacity: OffloadBandwidth: LowStack: StandardBottleneck: Host offload
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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) — 14.1 GB, 22.2 tok/s, Very compromised (needs ~1.3 GB host RAM)
14.1 GB required12.0 GB available
118% VRAM needed

2.1 GB over capacity — needs offload or smaller quantization

Fit status

Very compromised (needs ~1.3 GB host RAM)

Decode

22.2 tok/s

TTFT

8728 ms

Safe context

5K

Memory

14.1 GB / 12.0 GB

Offload

20%

Memory breakdown

Weights9.0 GB
KV Cache3.1 GB
Runtime0.9 GB
Headroom1.2 GB

See how fast it feels

See how fast it feelsPhi-4-reasoning-plus 14B on RTX 4080 Laptop 12GB
1st promptCold start — includes initialization
>Solve: If a train travels at 60 mph for 2.5 hours, how far does it go?
Let me work through this step by step. Given information: - Speed = 60 mph (miles per hour) - Time = 2.5 hours Formula: Distance = Speed x Time Calculation: Distance = 60 mph x 2.5 h = 150 miles The train travels 150 miles. Double-check: at 60 mph the train covers 60 miles each hour. In half an hour it covers 30 miles. So in 2.5 hours: 60 + 60 + 30 = 150 miles. Confirmed.
2nd promptWarm — model ready, no init overhead
>What if the train stops for 20 minutes halfway?
The stop doesn't change the total distance covered while moving, but it affects total trip time. Breakdown: - First half: 1.25 hours at 60 mph = 75 miles - Stop: 20 minutes (no distance) - Second half: 1.25 hours at 60 mph = 75 miles Total distance: 150 miles (same) Total time: 2.5 h + 0.33 h = 2.83 hours Average speed: 150 / 2.83 = 53 mph The distance stays the same but average speed drops to 53 mph because of the stop.
Estimated: 22.2 tok/s decode · 8.7s TTFT (warm) · 56 tok/s prefill

What limits this setup

It fits through host-memory offload, and offload is the main reason performance drops.

CPU or host-memory offload is active

About 20% of the working set spills out of accelerator memory, which usually hurts latency and sustained decode throughput.

Very little memory headroom

You can run the model, but there is not much room left for longer context, bigger batches, extra apps, or future model updates.

Best improvement path

Remove offload with more accelerator memory

Prioritize a GPU or unified-memory tier that fits the whole model natively. Removing offload usually helps more than small compute gains.

Buy headroom, not only minimum fit

A slightly larger memory tier gives you safer context growth and makes the recommendation more future-proof.

Increase host RAM if you keep offloading

This setup may need roughly 1.3 GB of extra host RAM just for the offloaded portion, before OS and other tools.

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatSRuns with offload (needs ~0.4 GB host RAM)28.2 tok/s3742 ms5K
CodingAVery compromised (needs ~1.3 GB host RAM)22.2 tok/s8728 ms5K
Agentic CodingFToo heavy14.7 tok/s19167 ms5K
ReasoningAVery compromised (needs ~1.3 GB host RAM)22.2 tok/s10315 ms5K
RAGFToo heavy14.7 tok/s23959 ms5K

Quantization options

How Phi-4-reasoning-plus 14B (14.699999809265137B params) fits at each quantization level on RTX 4080 Laptop 12GB (12.0 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
5.7 GB
LowS92
Q3_K_S
3
7.2 GB
LowS92
NVFP4Best for your GPU
4
8.2 GB
MediumS91
Q4_K_M
4
9.0 GB
MediumF0
Q5_K_M
5
10.6 GB
HighF0
Q6_K
6
12.1 GB
HighF0
Q8_0
8
15.7 GB
Very HighF0
F16
16
30.1 GB
MaximumF0

Get started

Copy-paste commands to run Phi-4-reasoning-plus 14B on your machine.

Run

ollama run phi4-reasoning

Frequently asked questions

Can RTX 4080 Laptop 12GB run Phi-4-reasoning-plus 14B?

Yes, RTX 4080 Laptop 12GB can run Phi-4-reasoning-plus 14B with a A grade (Very compromised (needs ~1.3 GB host RAM)). Expected decode speed: 22.2 tok/s.

How much VRAM does Phi-4-reasoning-plus 14B need?

Phi-4-reasoning-plus 14B (14.699999809265137B parameters) requires approximately 14.1 GB of memory with Q4_K_M quantization.

What is the best quantization for Phi-4-reasoning-plus 14B?

The recommended quantization for Phi-4-reasoning-plus 14B is Q4_K_M, which balances quality and memory efficiency.

What speed will Phi-4-reasoning-plus 14B run at on RTX 4080 Laptop 12GB?

On RTX 4080 Laptop 12GB, Phi-4-reasoning-plus 14B achieves approximately 22.2 tokens per second decode speed with a time-to-first-token of 8728ms using Q4_K_M quantization.

Can RTX 4080 Laptop 12GB run Phi-4-reasoning-plus 14B for coding?

For coding workloads, Phi-4-reasoning-plus 14B on RTX 4080 Laptop 12GB receives a A grade with 22.2 tok/s and 5K context.

What context window can Phi-4-reasoning-plus 14B use on RTX 4080 Laptop 12GB?

On RTX 4080 Laptop 12GB, Phi-4-reasoning-plus 14B can safely use up to 5K tokens of context. The model's official context limit is 33K, but available memory constrains the safe maximum.

What should I upgrade first if Phi-4-reasoning-plus 14B feels slow on RTX 4080 Laptop 12GB?

Remove offload with more accelerator memory. Prioritize a GPU or unified-memory tier that fits the whole model natively. Removing offload usually helps more than small compute gains.

See all results for RTX 4080 Laptop 12GBSee all hardware for Phi-4-reasoning-plus 14B
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