Can Gemma 3 12B run on RTX 5080 16GB?

YES — Tight Fit

A83Great

Estimated from fit model

Gemma 3 12B needs ~15.0 GB VRAM. RTX 5080 16GB has 16.0 GB. With Q4_K_M quantization, expect ~90 tok/s.

Runtime: OllamaCapacity: TightBandwidth: HighStack: BasicBottleneck: Balanced

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) — 15.0 GB, 89.5 tok/s, Tight fit

15.0 GB required16.0 GB available

94% VRAM used

Fit status

Tight fit

Decode

89.5 tok/s

TTFT

2163 ms

Safe context

19K

Memory

15.0 GB / 16.0 GB

Memory breakdown

Weights7.3 GB

KV Cache4.9 GB

Runtime1.2 GB

Headroom1.6 GB

See how fast it feels

See how fast it feelsGemma 3 12B on RTX 5080 16GB
1st promptCold start — includes initialization
>Write a Python function to sort a list
Here's a Python function that sorts a list using quicksort:

def quicksort(arr):
    if len(arr) <= 1:
        return arr
    pivot = arr[len(arr) // 2]
    left   = [x for x in arr if x < pivot]
    middle = [x for x in arr if x == pivot]
    right  = [x for x in arr if x > pivot]
    return quicksort(left) + middle + quicksort(right)

# Example usage
numbers = [3, 6, 8, 10, 1, 2, 1]
print(quicksort(numbers))  # [1, 1, 2, 3, 6, 8, 10]

The algorithm picks a pivot, partitions the list into smaller, equal, and larger elements, then recursively sorts each partition and concatenates the results.
2nd promptWarm — model ready, no init overhead
>Now add type hints and a docstring
def quicksort(arr: list[int]) -> list[int]:
    """Sort a list using the quicksort algorithm.

    Args:
        arr: List of integers to sort.

    Returns:
        A new sorted list.
    """
    if len(arr) <= 1:
        return arr
    pivot = arr[len(arr) // 2]
    left   = [x for x in arr if x < pivot]
    middle = [x for x in arr if x == pivot]
    right  = [x for x in arr if x > pivot]
    return quicksort(left) + middle + quicksort(right)

Added type hints for the input and return type, plus a Google-style docstring.
Estimated: 89.5 tok/s decode · 2.2s TTFT (warm) · 224 tok/s prefill

What limits this setup

This setup is broadly balanced for this model.

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

Buy headroom, not only minimum fit

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

Performance by workload

Workload	Grade	Fit	Decode	TTFT	Context
Chat	S	Runs well	89.5 tok/s	1180 ms	19K
Coding	A	Tight fit	89.5 tok/s	2163 ms	19K
Agentic Coding	F	Too heavy	43.9 tok/s	6410 ms	19K
Reasoning	A	Tight fit	89.5 tok/s	2556 ms	19K
RAG	F	Too heavy	43.9 tok/s	8013 ms	19K

Quantization options

How Gemma 3 12B (12B params) fits at each quantization level on RTX 5080 16GB (16.0 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	4.7 GB	Low	A78
Q3_K_S	3	5.9 GB	Low	A79
NVFP4	4

Get started

Copy-paste commands to run Gemma 3 12B on your machine.

Run

ollama run gemma3:12b

Your hardware

More models your RTX 5080 16GB can run

Model	Params	Grade	Decode	Capabilities
Qwen 3 14B	14B	S	78.9 tok/s
Phi-4-reasoning-plus 14B	14.7B	S	74.8 tok/s

Frequently asked questions

Can RTX 5080 16GB run Gemma 3 12B?

Yes, RTX 5080 16GB can run Gemma 3 12B with a A grade (Tight fit). Expected decode speed: 89.5 tok/s.

How much VRAM does Gemma 3 12B need?

Gemma 3 12B (12B parameters) requires approximately 15.0 GB of memory with Q4_K_M quantization.

What is the best quantization for Gemma 3 12B?

The recommended quantization for Gemma 3 12B is Q4_K_M, which balances quality and memory efficiency.

What speed will Gemma 3 12B run at on RTX 5080 16GB?

On RTX 5080 16GB, Gemma 3 12B achieves approximately 89.5 tokens per second decode speed with a time-to-first-token of 2163ms using Q4_K_M quantization.

Can RTX 5080 16GB run Gemma 3 12B for coding?

For coding workloads, Gemma 3 12B on RTX 5080 16GB receives a A grade with 89.5 tok/s and 19K context.

What context window can Gemma 3 12B use on RTX 5080 16GB?

On RTX 5080 16GB, Gemma 3 12B can safely use up to 19K tokens of context. The model's official context limit is 131K, but available memory constrains the safe maximum.

What should I upgrade first if Gemma 3 12B feels slow on RTX 5080 16GB?

Buy headroom, not only minimum fit. A slightly larger memory tier gives you safer context growth and makes the recommendation more future-proof.

See all results for RTX 5080 16GB See all hardware for Gemma 3 12B

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