Can Falcon 40B Instruct run on AMD Instinct MI250X 128GB?

YES — Runs Great

B70Good

Estimated from fit model

Falcon 40B Instruct needs ~44.6 GB VRAM. AMD Instinct MI250X 128GB has 128.0 GB. With Q5_K_M quantization, expect ~96 tok/s.

Runtime: OllamaCapacity: RoomyBandwidth: 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

Q5_K_M (High quality) — 44.6 GB, 96.1 tok/s, Runs well

44.6 GB required128.0 GB available

35% VRAM used

Fit status

Runs well

Decode

96.1 tok/s

TTFT

2014 ms

Safe context

Memory

44.6 GB / 128.0 GB

Memory breakdown

Weights28.8 GB

KV Cache1.8 GB

Runtime1.2 GB

Headroom12.8 GB

See how fast it feels

See how fast it feelsFalcon 40B Instruct on AMD Instinct MI250X 128GB
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: 96.1 tok/s decode · 2.0s TTFT (warm) · 240 tok/s prefill

What limits this setup

This setup is broadly balanced for this model.

No major red flags

This recommendation has enough memory headroom and acceptable estimated speed for the selected workload.

Best improvement path

Performance by workload

Workload	Grade	Fit	Decode	TTFT	Context
Chat	B	Runs well	96.1 tok/s	1098 ms	8K
Coding	B	Runs well	96.1 tok/s	2014 ms	8K
Agentic Coding	A	Runs well	96.1 tok/s	2929 ms	8K
Reasoning	B	Runs well	96.1 tok/s	2380 ms	8K
RAG	A	Runs well	96.1 tok/s	3662 ms	8K

Inference speed

Falcon 40B Instruct inference speed — tokens per second by GPU & Mac

Estimated decode speed (tokens/sec) for Falcon 40B Instruct at Q5_K_M across popular GPUs and Apple Silicon, including multi-GPU rigs, using the fastest local runtime per device. Fastest is 2× RX 7900 XTX 24GB at ~45 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 / Mac	Memory	Quant	Speed (tok/s)	Fits?
2× RX 7900 XTX 24GB	48 GB	Q5_K_M	45.3	Fits
2× RTX 4090 24GB	48 GB	Q5_K_M	41.3	Fits
2× RTX 3090 24GB	48 GB	Q5_K_M	35.3	Fits
4× RTX 3060 12GB	48 GB	Q5_K_M	31.1	Fits
RTX 5090 32GB	32 GB	Q5_K_M	29.4	Heavy offload
MacBook Pro M4 Max 128GB	128 GB	Q5_K_M	23.1	Fits
MacBook Pro M4 Max 64GB	64 GB	Q5_K_M	23.1	Tight
Mac Studio M3 Ultra 256GB	256 GB	Q5_K_M	21.5	Fits
Mac Studio M2 Ultra 128GB	128 GB	Q5_K_M	17.9	Fits
Mac Studio M1 Ultra 128GB	128 GB	Q5_K_M	16.9	Fits
MacBook Pro M4 Pro 48GB	48 GB	Q5_K_M	12.9	Offloads
RTX 4090 24GB	24 GB	Q5_K_M	10.5	Too big
RX 7900 XTX 24GB	24 GB	Q5_K_M	9.5	Too big
MacBook Pro M3 Max 64GB	64 GB	Q5_K_M	9.2	Tight
RTX 3090 24GB	24 GB	Q5_K_M	9.0	Too big
MacBook Pro M1 Max 64GB	64 GB	Q5_K_M	8.5	Tight
RTX 4080 Super 16GB	16 GB	Q5_K_M	3.7	Too big
RTX 4070 12GB	12 GB	Q5_K_M	2.2	Too big
RTX 3060 12GB	12 GB	Q5_K_M	2.0	Too big
RTX 4060 8GB	8 GB	Q5_K_M	2.0	Too 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 Falcon 40B Instruct (40B params) fits at each quantization level on AMD Instinct MI250X 128GB (128.0 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	15.6 GB	Low	B59
Q3_K_S	3	19.6 GB	Low	B60
NVFP4	4	22.4 GB	Medium	B60
Q4_K_M	4	24.4 GB	Medium	B60
Q5_K_M	5	28.8 GB	High	B61
Q6_K	6	32.8 GB	High	B62
Q8_0	8	42.8 GB	Very High	B63
F16Best for your GPU	16	82.0 GB	Maximum	B68

Get started

Copy-paste commands to run Falcon 40B Instruct on your machine.

Run

docker run --rm -it ghcr.io/ggerganov/llama.cpp:full \
  --hf-repo "tiiuae/falcon-40b-instruct" \
  --hf-file "falcon-40b-instruct-Q5_K_M.gguf" \
  -c 4096 -ngl 99

Frequently asked questions

Can AMD Instinct MI250X 128GB run Falcon 40B Instruct?

Yes, AMD Instinct MI250X 128GB can run Falcon 40B Instruct with a B grade (Runs well). Expected decode speed: 96.1 tok/s.

How much VRAM does Falcon 40B Instruct need?

Falcon 40B Instruct (40B parameters) requires approximately 44.6 GB of memory with Q5_K_M quantization.

What is the best quantization for Falcon 40B Instruct?

The recommended quantization for Falcon 40B Instruct is Q5_K_M, which balances quality and memory efficiency.

What speed will Falcon 40B Instruct run at on AMD Instinct MI250X 128GB?

On AMD Instinct MI250X 128GB, Falcon 40B Instruct achieves approximately 96.1 tokens per second decode speed with a time-to-first-token of 2014ms using Q5_K_M quantization.

Can AMD Instinct MI250X 128GB run Falcon 40B Instruct for coding?

For coding workloads, Falcon 40B Instruct on AMD Instinct MI250X 128GB receives a B grade with 96.1 tok/s and 8K context.

What context window can Falcon 40B Instruct use on AMD Instinct MI250X 128GB?

On AMD Instinct MI250X 128GB, Falcon 40B Instruct can safely use up to 8K tokens of context. The model's official context limit is 8K, but available memory constrains the safe maximum.

See all results for AMD Instinct MI250X 128GB See all hardware for Falcon 40B Instruct

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