Falcon 40B Instruct needs ~44.9 GB VRAM. NVIDIA DGX Spark 128GB has 108.8 GB. With Q5_K_M quantization, expect ~6 tok/s.
Operating mode
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.
Select quantization to explore
Fit status
Runs well
Decode
6.3 tok/s
TTFT
30687 ms
Safe context
8K
Memory
44.9 GB / 108.8 GB
The model fits in shared memory, but shared-memory bandwidth is now the real limiter.
Fit does not mean dedicated-VRAM speed
Unified or shared memory can make a model technically fit, but sustained tokens per second may still trail a discrete high-bandwidth GPU with less total memory.
Shared-memory contention still exists
The OS, browser, and inference runtime all compete for the same physical memory pool, so real-world headroom is less forgiving than raw capacity suggests.
Prioritize bandwidth, not only capacity
If this workload feels slow, the next useful step is often a GPU tier with materially faster memory bandwidth rather than only a small bump in capacity.
| Workload | Grade | Fit | Decode | TTFT | Context |
|---|---|---|---|---|---|
| Chat | B | Runs well | 6.3 tok/s | 16738 ms | 8K |
| Coding | B | Runs well | 6.3 tok/s | 30687 ms | 8K |
| Agentic Coding | B | Runs well | 6.3 tok/s | 44636 ms | 8K |
| Reasoning | B | Runs well | 6.3 tok/s | 36266 ms | 8K |
| RAG | B | Runs well | 6.3 tok/s | 55795 ms | 8K |
How Falcon 40B Instruct (40B params) fits at each quantization level on NVIDIA DGX Spark 128GB (92.2 GB usable).
| Quant | Bits | VRAM | Quality | Fit |
|---|---|---|---|---|
Q2_K | 2 | 15.6 GB | Low | B61 |
Q3_K_S | 3 | 19.6 GB | Low | B62 |
NVFP4 | 4 | 22.4 GB | Medium | B62 |
Q4_K_M | 4 | 24.4 GB | Medium | B62 |
Q5_K_M | 5 | 28.8 GB | High | B63 |
Q6_K | 6 | 32.8 GB | High | B64 |
Q8_0Best for your GPU | 8 | 42.8 GB | Very High | B66 |
F16 | 16 | 82.0 GB | Maximum | F0 |
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升级选项
NVIDIA H200 141GB经济之选Raises estimated decode speed by about 2365%.
Adds memory headroom for longer context windows and future model growth.
~$30,000 MSRP
NVIDIA H200 PCIe 141GB最佳性价比Raises estimated decode speed by about 2365%.
Adds memory headroom for longer context windows and future model growth.
~$30,000 MSRP
NVIDIA B200 180GBNVIDIA 升级Raises estimated decode speed by about 4008%.
Adds memory headroom for longer context windows and future model growth.
~$30,000 MSRP
Yes, NVIDIA DGX Spark 128GB can run Falcon 40B Instruct with a B grade (Runs well). Expected decode speed: 6.3 tok/s.
Falcon 40B Instruct (40B parameters) requires approximately 44.9 GB of memory with Q5_K_M quantization.
The recommended quantization for Falcon 40B Instruct is Q5_K_M, which balances quality and memory efficiency.
On NVIDIA DGX Spark 128GB, Falcon 40B Instruct achieves approximately 6.3 tokens per second decode speed with a time-to-first-token of 30687ms using Q5_K_M quantization.
For coding workloads, Falcon 40B Instruct on NVIDIA DGX Spark 128GB receives a B grade with 6.3 tok/s and 8K context.
On NVIDIA DGX Spark 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.
Prioritize bandwidth, not only capacity. If this workload feels slow, the next useful step is often a GPU tier with materially faster memory bandwidth rather than only a small bump in capacity.
Not always. NVIDIA DGX Spark 128GB can often fit larger models thanks to unified memory, but a discrete GPU with dedicated high-bandwidth VRAM may still decode faster once the model fits. For this combination, the important distinction is capacity versus sustained throughput.
Paste this snippet into any page to show a live fit card.
<iframe src="https://willitrunai.com/embed/falcon-40b-instruct-on-dgx-spark-128gb" 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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