Can OpenChat 7B run on RX 580 8GB?

YES — With Offload

C52Usable

Estimated from fit model

OpenChat 7B needs ~7.9 GB VRAM. RX 580 8GB has 8.0 GB. With Q4_K_M quantization, expect ~28 tok/s.

Runtime: llama.cppCapacity: OffloadBandwidth: LowStack: StandardBottleneck: 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) — 7.9 GB, 27.7 tok/s, Runs with offload

7.9 GB required8.0 GB available

99% VRAM used

Fit status

Runs with offload

Decode

27.7 tok/s

TTFT

6986 ms

Safe context

Memory

7.9 GB / 8.0 GB

Memory breakdown

Weights4.3 GB

KV Cache2.0 GB

Runtime0.9 GB

Headroom0.8 GB

See how fast it feels

See how fast it feelsOpenChat 7B on RX 580 8GB
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: 27.7 tok/s decode · 7.0s TTFT (warm) · 69 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.

Older PCIe generation

PCIe 3.0 is workable, but it compounds the penalty when you offload heavily or try to scale across multiple cards.

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	C	Tight fit	27.7 tok/s	3810 ms	8K
Coding	C	Runs with offload	27.7 tok/s	6986 ms	8K
Agentic Coding	F	Too heavy	12.7 tok/s	22126 ms	8K
Reasoning	C	Runs with offload	27.7 tok/s	8256 ms	8K
RAG	F	Too heavy	12.7 tok/s	27658 ms	8K

Quantization options

How OpenChat 7B (7B params) fits at each quantization level on RX 580 8GB (8.0 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	2.7 GB	Low	B55
Q3_K_S	3	3.4 GB	Low	B56
NVFP4	4	3.9 GB	Medium	B55
Q4_K_M	4	4.3 GB	Medium	B55
Q5_K_MBest for your GPU	5	5.0 GB	High	C55
Q6_K	6	5.7 GB	High	F0
Q8_0	8	7.5 GB	Very High	F0
F16	16	14.3 GB	Maximum	F0

Get started

Copy-paste commands to run OpenChat 7B on your machine.

Run

ollama run openchat

Upgrade-Optionen

Hardware, die OpenChat 7B gut ausführt

RX 7600 XT 16GBGünstige Wahl

16 GB VRAM (+8)288 GB/s (+32)

Raises estimated decode speed by about 52%.42.1 tok/s Dekodierung

Raises estimated decode speed by about 52%.

Adds memory headroom for longer context windows and future model growth.

ca. $329 MSRP

RX 9060 XT 16GBBestes Preis-Leistungs-Verhältnis

16 GB VRAM (+8)320 GB/s (+64)

Raises estimated decode speed by about 83%.50.8 tok/s Dekodierung

Raises estimated decode speed by about 83%.

Adds memory headroom for longer context windows and future model growth.

ca. $349 MSRP

RX 7700 XT 12GBAMD-Upgrade

12 GB VRAM (+4)432 GB/s (+176)

Raises estimated decode speed by about 136%.65.3 tok/s Dekodierung

Raises estimated decode speed by about 136%.

Adds memory headroom for longer context windows and future model growth.

ca. $449 MSRP

Frequently asked questions

Can RX 580 8GB run OpenChat 7B?

Yes, RX 580 8GB can run OpenChat 7B with a C grade (Runs with offload). Expected decode speed: 27.7 tok/s.

How much VRAM does OpenChat 7B need?

OpenChat 7B (7B parameters) requires approximately 7.9 GB of memory with Q4_K_M quantization.

What is the best quantization for OpenChat 7B?

The recommended quantization for OpenChat 7B is Q4_K_M, which balances quality and memory efficiency.

What speed will OpenChat 7B run at on RX 580 8GB?

On RX 580 8GB, OpenChat 7B achieves approximately 27.7 tokens per second decode speed with a time-to-first-token of 6986ms using Q4_K_M quantization.

Can RX 580 8GB run OpenChat 7B for coding?

For coding workloads, OpenChat 7B on RX 580 8GB receives a C grade with 27.7 tok/s and 8K context.

What context window can OpenChat 7B use on RX 580 8GB?

On RX 580 8GB, OpenChat 7B can safely use up to 8K tokens of context. The model's official context limit is 8K, but available memory constrains the safe maximum.

What should I upgrade first if OpenChat 7B feels slow on RX 580 8GB?

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 RX 580 8GB See all hardware for OpenChat 7B

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<iframe src="https://willitrunai.com/embed/openchat-7b-on-rx-580-8gb" width="400" height="180" frameborder="0" style="border:none;border-radius:12px;overflow:hidden;" title="Will It Run AI — fit result"></iframe>

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