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URL: https://willitrunai.com/can-run/cerebras-gpt-13b-on-rtx-a4500-20gb


Can Cerebras-GPT 13B run on RTX A4500 20GB?

BARELY — Tight on Memory

B57Good
Estimated from fit model

Cerebras-GPT 13B needs ~22.3 GB VRAM. RTX A4500 20GB has 20.0 GB. With Q5_K_M quantization, expect ~32 tok/s.

Runtime: OllamaCapacity: OffloadBandwidth: MediumStack: 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.

Capabilities:

Select quantization to explore

Q5_K_M (High quality) — 22.3 GB, 32.4 tok/s, Very compromised (needs ~1 GB host RAM)
22.3 GB required20.0 GB available
112% VRAM needed

2.3 GB over capacity — needs offload or smaller quantization

Fit status

Very compromised (needs ~1 GB host RAM)

Decode

32.4 tok/s

TTFT

5981 ms

Safe context

12K

Memory

22.3 GB / 20.0 GB

Offload

10%

Memory breakdown

Weights9.4 GB
KV Cache9.8 GB
Runtime1.2 GB
Headroom2.0 GB

See how fast it feels

See how fast it feelsCerebras-GPT 13B on RTX A4500 20GB
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: 32.4 tok/s decode · 6.0s TTFT (warm) · 81 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 10% 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 1.0 GB of extra host RAM just for the offloaded portion, before OS and other tools.

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatBTight fit54.4 tok/s1941 ms12K
CodingBVery compromised (needs ~1 GB host RAM)32.4 tok/s5981 ms12K
Agentic CodingFToo heavy15.1 tok/s18674 ms12K
ReasoningBVery compromised (needs ~1 GB host RAM)32.4 tok/s7069 ms12K
RAGFToo heavy15.1 tok/s23343 ms

Quantization options

How Cerebras-GPT 13B (13B params) fits at each quantization level on RTX A4500 20GB (20.0 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
5.1 GB
LowB63
Q3_K_S
3
6.4 GB
LowB64
NVFP4
4

Get started

Copy-paste commands to run Cerebras-GPT 13B on your machine.

Run

docker run --rm -it ghcr.io/ggerganov/llama.cpp:full \ --hf-repo "cerebras/Cerebras-GPT-13B" \ --hf-file "Cerebras-GPT-13B-Q5_K_M.gguf" \ -c 4096 -ngl 99

Upgrade options

Hardware that runs Cerebras-GPT 13B well

👁 NVIDIA
RTX 3090 24GBBudget pick
24 GB VRAM (+4)936 GB/s (+296)
B
Removes host-memory offload, which is usually the single biggest latency and throughput win.71.4 tok/s decode

Removes host-memory offload, which is usually the single biggest latency and throughput win.

Raises estimated decode speed by about 120%.

~$1,499 MSRP

👁 NVIDIA
RTX 4090 24GBBest value
24 GB VRAM (+4)1008 GB/s (+368)
B
Removes host-memory offload, which is usually the single biggest latency and throughput win.83.5 tok/s decode

Removes host-memory offload, which is usually the single biggest latency and throughput win.

Raises estimated decode speed by about 158%.

~$1,599 MSRP

👁 NVIDIA
RTX A5500 24GBNVIDIA upgrade
24 GB VRAM (+4)768 GB/s (+128)
B
Removes host-memory offload, which is usually the single biggest latency and throughput win.65.3 tok/s decode

Removes host-memory offload, which is usually the single biggest latency and throughput win.

Raises estimated decode speed by about 102%.

~$3,200 MSRP

Frequently asked questions

See all results for RTX A4500 20GBSee all hardware for Cerebras-GPT 13B
12K
7.3 GB
Medium
B65
Q4_K_M
4
7.9 GB
MediumB65
Q5_K_M
5
9.4 GB
HighB66
Q6_K
6
10.7 GB
HighB67
Q8_0Best for your GPU
8
13.9 GB
Very HighB66
F16
16
26.7 GB
MaximumF0

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.