Can I run it?

Can I run Qwen3.5 2B on GeForce RTX 4090?

Runs great

Runs great fully on your GeForce RTX 4090 at BF16, 8K context, about 143–195 tok/s. Weights 3.52 GB plus 0.10 GB of KV cache — 3.95 GB of 22.3 GB usable. Up to 256K context still fits.

Qwen3.5 2B details · GeForce RTX 4090 page · How this estimate is made

Run commands

llama-server -hf unsloth/Qwen3.5-2B-GGUF:BF16 -c 8192 -ngl 24

ollama run qwen3.5

lms get unsloth/Qwen3.5-2B-GGUF
# Then load quant BF16

Assumptions

• Estimate, not a benchmark. Decode speed uses a memory-bandwidth model at 55–75% of peak.
• KV cache is FP16. Engine overhead assumes llama.cpp (0.3 GB + 1% of the weights). Ollama is closer to 0.9 GB + 3%, LM Studio closer to 1 GB + 3%.
• BF16 size is the real GGUF file size from Hugging Face.
• 0.5 GB is reserved because this GPU also drives a display, then 5% of the rest is left free.
• Speed is quoted at 8K context, not at the maximum context that still fits.

Larger models that also fit

• Can I run Qwen3.8 27B on GeForce RTX 4090? — Tight fit, UD-Q6_K, 25–34 tok/s
• Can I run gemma 4 12b it on GeForce RTX 4090? — Runs, UD-Q8_K_XL, 33–45 tok/s
• Can I run Qwen3.5 9B on GeForce RTX 4090? — Runs, BF16, 30–42 tok/s

Updated 2026-10-24. Profile on this page is the device default plus 32 GB of DDR5-5600 system RAM.