willitrun·ai

Can StarCoder 15B run on RX 7900 XT 20GB?

YES — With Q2_K

B60Good
Estimated from fit model

StarCoder 15B needs ~23.7 GB VRAM. RX 7900 XT 20GB has 20.0 GB. With Q2_K quantization, expect ~37 tok/s.

Runtime: OllamaCapacity: OffloadBandwidth: HighStack: BasicBottleneck: Host offload
Share:

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.

StarCoder 15B at Q5_K_M needs 28.6 GB — too much for RX 7900 XT 20GB (20.0 GB). Runs at Q2_K (23.7 GB) with low quality.
Capabilities:

Select quantization to explore

Q5_K_M (High quality) 28.6 GB, exceeds 20.0 GB available
28.6 GB required20.0 GB available
143% VRAM needed

8.6 GB over capacity — needs offload or smaller quantization

Fit status

Too heavy

Decode

16.0 tok/s

TTFT

12133 ms

Safe context

7K

Memory

28.6 GB / 20.0 GB

Offload

30%

Memory breakdown

Weights10.8 GB
KV Cache14.6 GB
Runtime1.2 GB
Headroom2.0 GB

See how fast it feels

With memory offload — actual speed may be lower
See how fast it feelsStarCoder 15B on RX 7900 XT 20GB
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: 16.0 tok/s decode · 12.1s TTFT (warm) · 40 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 0.9 GB of extra host RAM just for the offloaded portion, before OS and other tools.

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatBRuns with offload (needs ~0.7 GB host RAM)29.7 tok/s3555 ms7K
CodingFToo heavy16.0 tok/s12133 ms7K
Agentic CodingFToo heavy6.8 tok/s41412 ms7K
ReasoningFToo heavy16.0 tok/s14339 ms7K
RAGFToo heavy6.8 tok/s51765 ms7K

Inference speed

StarCoder 15B inference speed — tokens per second by GPU & Mac

Estimated decode speed (tokens/sec) for StarCoder 15B at Q5_K_M across popular GPUs and Apple Silicon, using the fastest local runtime per device. Fastest is RTX 5090 32GB at ~113 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 GBQ5_K_M113.4Tight
Mac Studio M3 Ultra 256GB
256 GBQ5_K_M52.6Fits
Mac Studio M2 Ultra 128GB
128 GBQ5_K_M43.8Fits
Mac Studio M1 Ultra 128GB
128 GBQ5_K_M41.6Fits
NVIDIARTX 4090 24GB
24 GBQ5_K_M36.3Too big
RX 7900 XTX 24GB
24 GBQ5_K_M32.8Too big
NVIDIARTX 3090 24GB
24 GBQ5_K_M31.1Too big
MacBook Pro M4 Max 128GB
128 GBQ5_K_M30.0Fits
MacBook Pro M4 Max 64GB
64 GBQ5_K_M30.0Fits
MacBook Pro M3 Max 64GB
64 GBQ5_K_M22.7Fits
MacBook Pro M1 Max 64GB
64 GBQ5_K_M20.8Fits
MacBook Pro M4 Pro 48GB
48 GBQ5_K_M18.3Tight
NVIDIARTX 4080 Super 16GB
16 GBQ5_K_M13.1Too big
NVIDIARTX 4070 12GB
12 GBQ5_K_M5.4Too big
NVIDIARTX 3060 12GB
12 GBQ5_K_M3.4Too big
NVIDIARTX 4060 8GB
8 GBQ5_K_M2.8Too big

Estimates for single-stream decoding at Q5_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 StarCoder 15B (15B params) fits at each quantization level on RX 7900 XT 20GB (20.0 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
5.9 GB
LowA73
Q3_K_S
3
7.4 GB
LowA74
NVFP4
4
8.4 GB
MediumA75
Q4_K_M
4
9.2 GB
MediumA75
Q5_K_M
5
10.8 GB
HighA76
Q6_K
6
12.3 GB
HighA76
Q8_0Best for your GPU
8
16.1 GB
Very HighA75
F16
16
30.7 GB
MaximumF0

Get started

Copy-paste commands to run StarCoder 15B on your machine.

Run

lms load starcoder && lms server start

Opciones de mejora

Hardware que ejecuta bien StarCoder 15B

Frequently asked questions

Can RX 7900 XT 20GB run StarCoder 15B?

Yes, RX 7900 XT 20GB can run StarCoder 15B at Q2_K quantization (Very compromised (needs ~0.9 GB host RAM)). The recommended Q5_K_M requires 28.6 GB which exceeds available memory, but at Q2_K it needs only 23.7 GB. Expected decode speed: 36.6 tok/s.

How much VRAM does StarCoder 15B need?

StarCoder 15B (15B parameters) requires approximately 28.6 GB at Q5_K_M quantization. On RX 7900 XT 20GB, it fits at Q2_K using 23.7 GB.

What is the best quantization for StarCoder 15B?

The recommended quantization is Q5_K_M, but on RX 7900 XT 20GB the best fitting quantization is Q2_K, which uses 23.7 GB.

What speed will StarCoder 15B run at on RX 7900 XT 20GB?

On RX 7900 XT 20GB, StarCoder 15B achieves approximately 36.6 tokens per second decode speed with a time-to-first-token of 5290ms using Q2_K quantization.

Can RX 7900 XT 20GB run StarCoder 15B for coding?

For coding workloads, StarCoder 15B on RX 7900 XT 20GB receives a F grade with 16.0 tok/s and 7K context.

What context window can StarCoder 15B use on RX 7900 XT 20GB?

On RX 7900 XT 20GB, StarCoder 15B can safely use up to 8K tokens of context at Q2_K quantization. The model's official context limit is 8K, but available memory constrains the safe maximum.

What should I upgrade first if StarCoder 15B feels slow on RX 7900 XT 20GB?

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 RX 7900 XT 20GBSee all hardware for StarCoder 15B
Embed this result

Paste this snippet into any page to show a live fit card.

<iframe src="https://willitrunai.com/embed/starcoder-15b-on-rx-7900-xt-20gb" width="400" height="180" frameborder="0" style="border:none;border-radius:12px;overflow:hidden;" title="Will It Run AI — fit result"></iframe>

Preview: