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Run LLM Locally

Phi-4 14B on the RTX 5090

With 32 GB of VRAM, the RTX 5090 runs Phi-4 14B at Q4_K_M entirely on the GPU with an 8K context (about 11.2 GB needed). At Q8_0 it fits entirely.

Phi-4 14B

Q4_K_M · 8K context

Excellent

The model needs about 11.2 GB and fits in the 31 GB available, with 19.8 GB to spare.

Your hardware
RTX 5090 32 GB · 64 GB RAM
Estimated memory
~11.2 GB estimate
VRAM (usable memory)
31 GB
GPU only
Yes
CPU/GPU offload
Not required
Generation speed
105–157 tok/s estimate
Largest context in fast memory
16K tokens
Confidence: low

Based on: memory bandwidth (1,792 GB/s) and model size

Memory breakdown

~11.2 GB (10.8 GB–11.8 GB) needed · estimate

Fits entirely in VRAM · 19.8 GB left

  • Model weights8.4 GB
  • KV cache1.6 GB
  • Runtime overhead0.7 GB
  • Safety margin0.5 GB
Assumptions: context 8K tokens · KV cache f16 · llama.cpp (CUDA) · flash attention on · weights = real file size

EstimateData updated 24 days agoSource: Run LLM Locally engine, Hugging Face config.json + model card

What makes this estimate less reliable

  • no benchmark for this hardware and model yet

Other quantizations on the RTX 5090

Phi-4 14B on RTX 5090 + 64 GB RAM · 8K context
Phi-4 14B Q8_08K~17.6 GB · 70–99 tok/s estimateExcellent
Phi-4 14B Q6_K8K~14.2 GB · 86–124 tok/s estimateExcellent
Phi-4 14B Q5_K_M8K~12.8 GB · 94–138 tok/s estimateExcellent
Phi-4 14B Q4_K_M8K~11.2 GB · 105–157 tok/s estimateExcellent
Phi-4 14B IQ4_XS8K~10.2 GB · 114–174 tok/s estimateExcellent
Phi-4 14B Q3_K_M8K~9.6 GB · 120–184 tok/s estimateExcellent

Alternatives

Where to buy a RTX 5090

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GeForce RTX 5090

32 GB GDDR7 · 1,792 GB/s · 575 W

ExcellentRuns Phi-4 14B Q4_K_M entirely in memory

Price not available

Availability unknown

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Frequently asked questions

Can the RTX 5090 run Phi-4 14B?
The model needs about 11.2 GB and fits in the 31 GB available, with 19.8 GB to spare.
Which quantization should I use on the RTX 5090?
Q8_0 is the highest-precision quantization that fits entirely in VRAM at 8K context. ~17.6 GB / 31 GB.
What is the largest context on the RTX 5090?
At Q4_K_M, about 16K tokens fit entirely in VRAM with an f16 KV cache. A q8_0 KV cache roughly doubles that.
How fast is Phi-4 14B (RTX 5090)?
We estimate 105–157 tok/s (estimate, confidence low). Based on: memory bandwidth (1,792 GB/s) and model size.